Even though his name was changed in the English versions, he is not related to Harabote Muscle in any of the versions of Ultimate Muscle. This is later revealed as a stage name, with his real name in the dub being Mantaro Kinnikuman.
Mantaro is the son of Kinniku Suguru and Bibimba, and is the current prince of Planet Kinniku. He is spoiled and prefers to play rather than fight and train. He is a serious lecher and will often try to sneak into cabarets and enjo kōsai cafes (this aspect is toned down in the anime, as he is only 14). After the Hercules Factory he was stationed in Beverly Park where he lived there with Meat
While Mantaro possess every aspect of his father's original potential and ability, he also has a LOT of the negative aspects of Suguru's personality. Mantaro is very cowardly and will often hesitate to fight, but when his friends are in trouble or his opponents are fighting unfairly, he musters up the courage to fight. When the fight reaches its climax, he evokes his hereditary Kajiba no Kuso Djikara (Burning Inner Strength) and the Niku Mark (肉マーク) appears on his forehead. He is named after Ultraman Taro (Ultraman + Taro). Because of this, in the early episodes of the anime he is often mistakenly called Kinnikuman Taro (キン肉マン・タロウ).
Because Suguru had his old fight records annulled, Mantaro never knew how great his father was until he met Meat. Mantaro uses his father's old techniques the Kinniku Buster and the Kinniku Driver until he develops his own finishing moves, the Muscle Millennium and the Muscle Gravity.
In the Japanese version of the anime, Mantaro has a habit of adding Muscle (マッスル, Massuru) at the end of certain words and sentences in place of the standard masu (ます). For example, Itadaki-masu (いただきます), a common Japanese phrase said before eating, becomes Itadaki-MUSCLE (いただきマッスル, Itadaki Massuru).
Mantaro is born to "The Legend of All Legends" Kinnikuman, the 58th King of Planet Kinniku, and his queen Bibinba. However, because Kinnikuman had his records annulled after becoming king, Mantaro is unaware of how great his father truly is until he meets Meat. Mantaro is trained by his father for most of his early childhood, but as Kinnikuman becomes increasingly busy ruling Planet Kinniku, his old friend Ramenman is brought in to finish Mantaro's basic training.  Ramenman has helped bring Mantaro's grades from a 0% to a 25%, as well as how to teach him the basics of wrestling and martial arts. When Ramenman is defeated by Bone Killer, Mantaro avenges him and defeats Bone Killer in his place, thus realising his potential. 
Despite of all of this, Mantaro grows up into a very spoiled, lazy, and cowardly prince (however, the fact that he was raised during peace times could also be a factor, as Kinnikuman admits they did not teach him to properly fight).  In the anime is shown that, despite growing with no trust or respect for his father, Mantaro cares deeply for his mother, treasuring her cooking as a sign of care for him.
In the manga, Kinnikuman drags Mantaro onto a ship that is set to board to the Hercules Factory. Mantaro meets Terry the Kid on board, who declares that he will not be number two (like his father), but will be number one and overtake Mantaro.  Mantaro injures himself during training, when Kid attacks him with a peanut to throw him off balance, and Specialman Jr. offers to take Mantaro to the infirmary. It is at this point Specialman Jr. reveals himself to be Anaconda in disguise. The Kid helps Mantaro, after Kinnikuman makes him realise that Terryman was never number two, but also a vital part of the team and a close friend. Mantaro defeats Anaconda with the Kid's help, and wins the cage match. 
Their final match is against the legends, whom they must defeat, and Mantaro is pitted against Kinnikuman.  Kinnikuman initially appears in his prime, but is revealed by Mantaro to be in bad shape, and Kinnikuman is mocked by his peers. The two engage in battle, which goes on for some time, until Mantaro gains the upper-hand and defeats his father in a fair battle. Mantaro wins the "Mask of Glory" from his father.  We next see Mantaro during the graduation ceremony, where all other candidates are celebrated, but we see Mantaro is very low in his grades and disrespected. He is commissioned to a Tokyo park, alongside Meat, as the best wrestler get the best turf to protect, and Mantaro feels insulted that his area of protection is a mere park. He argues with Robin Mask, but is ultimately ignored. 
Mantaro meets a newly awakened Meat in the park. They train for a while, but - when he attempts to leave his park - he is confronted by Gazelleman.  The two bicker and a fight is threatened, but Kevin Mask appears and attacks Gazelleman, and chastises the pair for their bad behaviour, at which point Mantaro tries to prevent him from harming Gazelleman. He pulls at Kevin's shirt, which rips it from his body and reveals his tattoo. They learn about Kevin's origins.  Kevin leaves, and later it is revealed Gazelleman has been injured by the dMP, who challenge the New Generation to a tournament. 
Tel-Tel Boy challenges Mantaro; this battle follows a scene where it is revealed Kevin Mask has sided with the dMp, along with flashbacks that explain why he ran away as a child.  Tel-Tel Boy makes the mistake of pretending to be Kinnikuman, as he assumes all children are scared of their parents, but he underestimates the relationship between father and son.  Mantaro is not scared of Kinnikuman and attacks in fervour, and eventually is able to win the match by breaking the ceiling of the dome and allowing rain to fry Tel-Tel Boy.  Mantaro feigns being injured, which leads to Seiuchin battling his next opponent in his place, Maxman. 
After Seiuchin is defeated, Mantaro takes his place in the ring.  He fights against MAXman, who is defeated by the worst enemy of a shoe: faeces.  This is changes to a "stink bug" in the English dub, with a flashback from Terry to explain the dangers of stink bugs, and this is ultimately what leads to Mantaro's victory. The defeat of these three dMp members leads to Kevin realising the error of his ways; he quits the dMp, but also rejects Mantaro's offer to join the Muscle League, and he goes on to become a lone wolf. 
After this match, Kid receives a message from The Nightmares. 
Kid is enraged that they have arrived in Osaka and defeated Gorgeousman and Barbarian.  He realises what it means to be a Seigi Chojin, but - the night before the first match against The Nightmares - is caught by their mentor/manager Sunshine in a topless bar (this was changed to him being caught skipping on a restaurant bill, in the anime, due to his age).  He is blackmailed into becoming the referee for the Terry the Kid vs. Rex King match. Mantaro first is a stickler for rules, leading Terry to suffer in his match and gain fouls, but eventually he allows Terry and opening which leads to Terry's victory in battle. 
The second match is Mantaro vs. Check Mate. It is revealed that Checkmate cannot feel pain, leading Mantaro to struggle in this match, but it is revealed he can still take damage. Kid - after seeing Checkmate attack a child and tear up Sunshine's only memento of his makeshift family - is reinvigorated and manages to turn the tides and defeat Checkmate.  This is followed by Sunshine destroyed the dMp base with a bomb and killing all remaining dMp members, as he takes Checkmate and helps him to recover. 
After Mantaro had defeated Checkmate and the d.M.p (along with some help of Terry the Kid), peace was restored once again. After which, Mantaro and his group had become apparently lazy and frequently took time off to relax while skipping training.  Harabote Muscle had become furious of the absence of the four Hercules Factory graduates and demanded why the four were repeatedly missing (in the English manga, Gorgeous Man stated that they were sick).  When Harabote found them, he had enough of their antics and had decided to have a tournament between the lazy four graduates (Mantaro Kinniku, Gazelleman, Terry the Kid, and Seiuchin) against the new graduates (Scarface, Jade, Clioneman and Dead Signal). 
Mantaro is first matched against Dead Signal, whom he defeats with relative ease.  He is the only one of his team to make it through to the second round, so he experiences immense pressure, but he faces Clioneman in his second round, where he finds inspiration from Seiuchin's defeat. Mantaro defeats Clioneman by urinating inside him, thus polluting his waters. 
During the Jade vs. Scarface match, Mantaro watches from the sidelines with Suzie and Dorothy. He is frustrated at the end by Scarface's treatment of a fellow Chojin, threatening to fight him, but Brocken Jr. stops Mantaro and gives to him Jade's skull badge.  Mantaro tries to show off during the Finals Eve celebrations, but instead makes a mess and embarrasses his teammates. He even goes as far as to play a game of strip rock-paper-scissors, much to the horror of Alexandria Meat. 
He goes on to the final match, where it is revealed that Scarface has secretly been Mars all along, and - not only this - he is a dMp member. Kevin watches from the stands and reveals that Mars tricked him into betraying his father and is a villain. Mantaro manages to defeat Mars, which saves his team from failure and prevents them from retraining at the Hercules Factory. 
First Love (Filler Arc)
After being neglected by his friends, Mantaro goes to a speed-dating event. There he meets Rinko Nikaido, whom he believes he loves at first sight, but Rinko rejects his advances and departs. Mantaro leaves on a date with a girl he thinks likes him, but is actually participating in 'compensated dating', and he rejects her in turn offended by 'immoral behaviour'. He is attacked by the girl's boyfriend, which Rinko witnesses, and - taking pity and admiring his moral code - she helps him and takes him on her bike to a place to rest. 
They arrive at Suminoe Kindergarten; Rinko tries to break back into her home, to avoid being caught past curfew, and it is revealed she is a delinquent and the daughter of Mari Nikaido. Meat arrives and reminisces with Mari.  Mantaro flirts with Rinko and - from that day onward - tries to gain her attention and follows her when possible, and it is revealed a friend of Rinko's is in trouble, so Rinko drags Mantaro to help find the friend and protect her from harm. Rinko is then captured by The Rigani. 
Mantaro wins the match with his Muscle Millennium and saves Rinko. 
It is revealed that Mantaro's elders think his skills/techniques lacking, those that worry in particular are Kinnikuman, Mayumi Kinniku, and Harabote Muscle.  They summon Ataru Kinniku to announce to Mantaro that he must learn the power of "Ultimate Muscle" (dub name).  This is an almost supernatural ability passed through the Kinniku bloodline that allows them to increase their strength, and can be measured through a lantern lit by three flames. Mantaro must light each flame by defeating a specific opponent in a three-round tournament devised by Ataru, at which point he will gain Ultimate Muscle. 
The first match is against Fork the Giant.  The second match is against Hanzo; in this match, we are introduced to The Ninja and the pasts of these two characters is explained via flashbacks, and the Ninja seeks to defeat Hanzo before Mantaro has a chance, but he is ultimately killed by Hanzo (this is changed to falling eternally in a bottomless pit in the dub).  Mantaro then defeats Hanzo in his place.  After this, he is matched against Bone Cold.  Bone Cold is revealed to be the son of Kinkotsuman, who was abused and turned evil, and - after Bone Cold murders Meat's father, Mince - Mantaro defeats him in turn with his Muscle Millennium.  It is then that Mantaro achieves Ultimate Muscle and succeeds in his tournament. 
Mantaro spends time celebrating with his friends, but they return to their home countries on the announcement of the Chojin Crown Resurrection.  He at first misses the chance to be the Japanese representative, by not taking part in the necessary competitions.  At first he nearly misses the preliminary matches for Japan, but - as The Nosonman is about to enter the final for his block - a series of mishaps harms every other competitor, which allows Mantaro the chance to compete against The Nosonman.  He ultimately wins the match and earns a spot as Japan's representative. 
He then goes on to participate in the preliminaries.
In the anime, these matches are simply a "Ha, You Looked!" and paper-rock-scissors match, followed by a 'first to the flag' style match, and lastly a three-legged race with a randomly chosen person.  In the manga, there are extra preliminary matches, which includes toppling a mountain of Daruma-style dolls, but these were cut from the anime perhaps due to time-constraints or the sometimes sexual nature by which Mantaro overcame the challenges, such as using his erection to topple the dolls.  At the end of the preliminaries, there is a big event to announce match-ups for the tournament itself, which is where the Poison Six-Pack arc begins in the anime.
[Poison Six-Pack Arc occurs here].
The Olympics continue as planned, with Mantaro taking part in a series of matches. He defeats Wash Ass by defecating inside of him in the manga, but this is changed to Mantaro chiselling out the inside of his bowl and using the beef-rice container to block his water-flow in the anime.  He later goes on to battle Barrierfreeman,  followed by Ricardo; the latter of which is revealed to be innately evil, despite his attempts to be good, and is never seen again after his defeat.  The final match is Kevin Mask vs. Mantaro Kinniku.In the manga, this match leads to Mantaro's defeat and a valuable lesson learned, which changes his character into a more mature and evolved person, and sparks a pivotal change in his character from that point forward, as he trains to be a better Chojin and regain his honour. In the anime, this was changed to Mantaro winning against Kevin in order to fit the American narrative of the "hero winning the day", as it was a series commissioned by the American 4Kids. The events otherwise play rather similar, but this is the very last arc of the anime and his victory does provide closure when otherwise closure would have been lacking.
While Mantaro is recovering from his loss to Kevin Mask at the Choujin Olympics, Reborn Ashuraman and the Demon Seed separate Meat's body into six pieces.  Their aim is to use the parts to revive General Terror, but Mantaro can win them back by defeating the Demon Seed members.  His first match is against 4D fighter The Constellation, who had already defeated Legend Buffaloman with ease.  Mantaro has a hard fight against Constellation's 4D powers. He eventually sets him up for the Muscle Millennium, but Constellation is able to escape it.  Mantaro begins to give up, but his No. 1 fan Kuan encourages him and cheers him on all in a manner similar to Meat, and he regains his power.  He then defeats Constellation with an incomplete Muscle Gravity. 
After the first fight Mantaro is too exhausted to continue, but luckily Hanzo, Ilioukhine, and Barrierfreeman arrive to fill in for him.  Mantaro watches from the sidelines (along with Rinko, Kid, Seiuchin, Gazelleman, Check, Jade, Jacqueline, and later, his father Kinnikuman) as one by one they all defeat their opponents but still end up dying (for different reasons). During the tag between the Blood Evolutions (Kevin Mask and Scarface) and The Demolitions (Reborn Asuraman and Voltman), Mantaro watches for a way to defeat Asuraman's Ultimate Ashura Buster. After the match ends and Scar is killed, a rematch is set with Mantaro teaming up with Kevin as The Botchan's (ザ・坊ちゃんズ).  They are given a few days to train for the fight, so Mantaro trains with Kid, Seiuchin, and Gazelleman. Unfortunately, he is unable to discover a way to defeat the Ultimate Asura Buster.
The day of the rematch comes and Kevin and Mantaro enter the Demon Womb, fighting in a ring atop hundreds of Choujin corpses, including the fallen Idol Choujin.  As the fight gets underway it soon becomes a handicap match against Voltman. Eventually they are able to defeat Voltman with their combo technique the Niku→Lap.  Kevin saves Meat's right leg but then passes out from exhaustion, falling out of the ring and to his death.  Mantaro is upset that Kevin has died, but is relieved that another piece of Meat has not been added to General Terror. But then Asuraman cuts off his own leg for General Terror and is given a metal prosthetic leg. As the fight continues, Mantaro still can't find a way to defeat the Ultimate Asura Buster, but when Asuraman's past is revealed he becomes shaken up enough that Mantaro gains an opportunity to defeat him with a Complete Muscle Gravity.
He then puts Meat back together and revives his fallen comrades with the Reborn Diamond.
One day, while he is supposed to be sparring with the other Idol's, Mantaro daydreams about being beat up by Kinnikuman and Terryman. Later, he is one of the 8 Time Warp Chojins and travels back in time to the days of the Legends (right after the Dream Chojin Tag Arc conclusion) in order to save Robin Mask from being killed and, by extension, Kevin Mask from being erased from time. He is initially made part of Barrierfreeman's Team 3, in charge of finding the Time Chojin's horns. Mantaro stumbles across the horns after Kid smacks a dirty magazine out of his and Barrier's hands. As they are boarding the time-ship, Mantaro tries to smuggle all of his toys and junk food, but Meat and Gazelleman reduce his luggage to the essentials. On the ship, Kid puts him on trash duty but soon sends him outside to remove a headstone (believed to be Chaos') from blocking the flight path. Before going back inside, Mantaro takes out a pack of sauce and writes The Kevin Mask (ケビン・マスク号, Kebin Masuku Go) on the side of the ship.
Upon arrival in 1983, Mantaro and Terry stop Lightning and Thunder from killing Robin, but immediately arouse suspicion from Kinnikuman and the other Legends. During the confusion, the Time Chojins try to kill Robin with the Death Watch Branding. While rushing to save Robin, Mantaro accidentally bumps Alisa (Robin's wife) into the Tag Trophy, causing her to bounce off and fall into the Death Watch Branding. Lightning takes advantage of this and thanks Mantaro for the "support", further convincing the Legends that the New Generation are evil. When the Ultimate Chojin Tag Tournament is announced, Mantaro tries to team up with Kid as the New Century Machineguns, but he refuses. After Seiuchin joins with Neptuneman, Mantaro is the only one without a partner. With help from 20th Century Meat, he learns of a legendary hero who protects the earth from Akugyo Chojin while the Legends are settling into retirement. This man is alive and living in Japan today (1983), but before they can learn his name, Mantaro unknowingly uses the page about him in the Choujin Encyclopedia as toilet paper.
Mantaro later teams with Chaos Avenir, who they believe to be the mystery Chojin. This leads to Mantaro befriending him, along with an implied romance stirring between Rinko and Chaos, and Rinko grows to be particularly close to Chaos in specific. Mantaro enters the Tag-Team tournament, where he wins a match against Hell Carpenters and later against the 20 Million Powers. He wins against The Machineguns with Kevin Mask replacing his former teammate, Chaos, when Chaos is murdered. Kevin and Mantaro eventually win the final round against the Five Disasters. They go on to return to their present time. This ends the manga.
(More to Come)
It is revealed that Kevin Mask was once an Akugyo Chojin, but - after changing his ways - joined a special programme at a chojin prison that allowed him to rehabilitate within five months.  Mantaro and Meat are ordered to monitor him on his release. Kevin immediately attacks Mantaro on sight of him outside of the prison, but Mantaro manages to counter all of his moves. He uses a Tower Bridge, but drops Mantaro when the guards threaten to throw him back into prison. 
(More to Come)
(More to Come)
When the chojin are allowed to pick their opponents for their first matches, Okan picks Mantaro Kinniku.  The match takes place in the basement level of the Misetan Department Store, Shinjuku, Tokyo.  The only main characters in attendance - as audience members - are Rinko Nikaido and Ikemen Muscle. The match begins with a Palm Rush from Okan against Mantaro's face, followed by a series of Middle Kicks and a High Kick. 
It is revealed she is embarrassed when Mantaro witnesses her lower undergarments, and - sensing her embarrassment - he proceeds to grope her breasts to embarrass her further.  He attempts a German Suplex, but Okan counters with a Forward Roll and an Ankle Hold. 
Okan follows with an Okan Sheets Ring. Mantaro is nearly about to give up the fight, when his back and legs are at risk of breaking, but an alarm clock falls from Okan's basket and Kinnikuman accidentally sets if off at 10am.  This triggers Okan to hang up her washing on a lineat the side of the ring. Mantaro realises that the sexist stereotype of all mothers being the same applies to Okan, who has lost all individual identity and is defined solely as a 'mother', and thus sets the clock to ring for 2pm, which triggers her into taking a nap: "the universal nap-time for mothers". 
Mantaro uses this opportunity to perform a Guillotine Drop.  He proceeds to throw her into the air, before he uses the Muscle Millennium to defeat her and end the match. The 3pm alarm rings, and - as all apparently good mothers do - Okan obediently obeys the alarm to pick her children up from school, with no animosity towards Mantaro or regret at losing the match, but does ask for a rematch when she "gets some time in [her] schedule". Okan leaves with her basket. 
(More to Come)
The placement for the semi-finals are decided by rock-paper-scissors.  Tentacles is forced to pick 'rock' due to only having tentacles, and so Mantaro Kinniku jams chopsticks into his flesh, which allows him to use 'scissors' at last moment. Together, they choose platform one. The match will take place at Shinbashi Station, where the ring is made of a takoyaki tray.  A flame is lit beneath the tray, while the holes are filled with dumpling batter, and various ingredients are dropped into the batter. The losing competitor will be used for the meat in the takoyaki. 
Mantaro is thrown first into the batter.  Sunshine and Ikemen Muscle start to shake the tray, which makes it harder for Mantaro to escape, but - as the takoyaki is complete - he frees himself from eating his way out of the batter. The holes are refilled and Mantaro tries to throw Tentacles into the mixture. Tentacles uses his Mimic Body to hide as a corner-post, which then flies out to strike Mantaro. Tentacles then pretends to be beef teriyaki to get inside Mantaro's body.  He gets fully inside Mantaro's body via his mouth.  Tentacles is unable to explode outward, as it is revealed Mantaro has a layer of dirt all over his body (due to not bathing or washing within the previous six months due to a hatred of baths). 
Tentacles - in disgust - flees from his body. Mantaro takes this opportunity to use his Kinniku Driver, propelling Tentacles into one of the holes filled with batter. He is baked into the batter and expelled from the ring, but Mantaro stops the audience from eating Tentacles by claiming he wishes to eat him as the victor.  Later, due to Mantaro saving him, he is able to burst forth from his dumpling. 
(More to Come)
Mantaro runs away from his match with Doomman. 
Okan is offered a selection of free samples, but soon eats them all in a single bite, and - after spotting Mantaro in disguise, trying to hide - pins him to a wall with the skewers upon which the samples came. Okan removes his disguise and holds him so that he cannot run away, and then asks him for help in picking ingredients for her stew.  Mantaro is surprised when she empties the cart and picks the dirty "bargain" vegetables.  After cleaning one off, she forces Mantaro to try a bite; to his surprise it tastes much better than the good-looking and clean vegetables. Okan says that this is a lesson true of wrestling. 
Mantaro may look rough, but he has pure and true talent, and The Doomman may look fancy and experienced, but he still lacks something at his core that makes him a true chojin. Okan reminds him that the important part about being a chojin is defending people from the forces of evil. This inspires Mantaro to change his ways and become a better chojin.  At the end of the tournament, Okan - along with the other Justice Chojin, including the new characters - join him as a large team and fight evil together. 
(More to Come)
Doomman starts strong with an upper-hand, getting in a series of blows and hurting Mantaro with a Dragon Suplex, which he follows with a Doom Ball.  With Okan's support, Mantaro manages to counter several of Doomman's moves.  It is revealed that Doomman obtained his powers from Satan, and - as he fights with his evil side - injures the cat he previously loved. He shreds the edges of the mat, creating a whirlpool structure around the edges of the mortar.  Doomman rolls down this structure, where he attacks with his Meteor Slice.  Doomman starts to gain the upper-hand again, but his brutality causes a member of the audience to throw a bottle at him; his cat jumps to protect him, which hits the cat. 
This brings out Doomman's humanity, as he nearly castrates the man that harmed his cat.  He nurses his cat and his armour parts from his body, and - after another flashback to his deal with Satan - Mantaro is able to gain an advantage.  This leads to an exchange of blows.  Doomman regains more of his humanity, as his cat starts to paw for him in sympathy and offer its support, and Doomman reneges on his pledge to Satan, removing the crosses of his Meteor Slicer as proof of his change of ways.  They then engage in a fair-match, which results in Mantaro nearly ending the match with his Muscle G technique. 
Ramenman prevents Ikemen Muscle from calling the end of the match, which leads to Doomman throwing away the rest of his anger and pledging himself to the Seigi Chojin, and finally Mantaro wins with a Pile Driver technique.  In the epilogue, Ramenman gives Doomman his medal for second-place and Mantaro helps him to stand when he needs support.  A month later, Mantaro leads the New Generation - including those like Okan and Fiona - in new adventures and protecting the world, as a team. 
In the anime, Mantaro is accidentally transported to Earth (as opposed to travelling immediately to the Hercules Factory alongside Kinnikuman). He defeats Bone Killer, who randomly attacks him in the park where he awakes Alexandria Meat from cryogenic slumber, and then is transported - along with Meat Alexandria - to the Hercules Factory, where he is subjected to strenuous training, and where he meets his future friends: Gazelleman, Terry the Kid, and Seiuchin. He initially has an intense rivalry with Terry, but they grow to become friends steadily over time. These three friends become strong supporting characters in the anime, featuring in their own filler arc.
(N.B. This arc takes place after the preliminaries of the Chojin Olympics Resurrection).
After the Chojin Crown prelims are finished, a group of Akugyou Chojin, known as the Poison Six Pack, kidnap Rinko, Keiko and Tamaki. Tag Team matches are held around the base of Mount Fuji, with the girls used as hostages, held in a floating jester head.
In both matches, Mantaro plays a key role in helping his team mates. In the first one, when Terry the Kid is under Dazzle's gaint eye trance, Mantaro uses feces to cause Kid to break out of his trance. When Kid and Jade knock out Dazzle and The Protector, Mantaro makes an attempt to catch the falling Tamaki, but misses. In the second match, Mantaro uses a spanking gesture to make Gazelleman clue into Puri-Puri Man's weakness. Mantaro also makes an attempt to save Seiuchin's mother and sister, but fails after almost drowning. After the last two members of the Six Pack are revealed, Mantaro vows to rescue Rinko in the next match.
Mantaro is teamed up with Kevin Mask in the last match of the Poison Six Pack. Kevin Mask defeats The Cyborg but is twenty-one seconds out of the ring, leaving Mantaro alone to deal with Baron Maximillion. At first, due to the Baron's skinny body, Mantaro thinks the match will be a cinch, however, using magic to avoid Mantaro's attacks, the Baron gains the upper hand, until Meat tells Mantaro to catch the Baron before he reappears again. Mantaro does this, and makes the Baron turn into his second form. As Maximillion pummels Mantaro, Kinniku Suguru appears to encourage Mantaro to fight on, and uses Rinko as encouragement, such as saying she is his future wife.
Powering up, Mantaro starts to win, until Maximillion turns into his last form. After using the finishing move, Baron Tornado Bomb, Mantaro has seemed to have lost, but starts to fight again. Suguru says he's Sleep Fighting, and by reflexes, reverses Max-a-Million's moves. His teammates, Rinko, Keiko and Tamaki, along with the entire spectators, cheer on Mantaro. In Mantaro's mind, Mantaro is sitting with the spirits of The Ninja and Mince, who convince him to keep fighting. Fully powered, Mantaro defeats the Baron with the Muscle Millennium. However, the jester head explodes, sending Rinko flying over the edge of Mount Fuji's crater. Mantaro chases after her, using a massive fart to catch up to her.
With Rinko saved thanks to the help of his friends, Mantaro works up the courage to ask Rinko for a kiss. Rinko is about to kiss him, but places Nakano-san in front of her, making Mantaro kiss him instead. Rinko's whispering is drowned out by the jester head exploding, and Mantaro tries to make Rinko repeat herself.
The preliminary matches for each country have been tweaked, insofar as each country only has one participant, as opposed to several participants chosen by blocks of matches, and so Mantaro loses out on being the Japanese representative as the representative has been chosen. There is instead a 'Wild Card' competition, in which is a random entry assigned to any nationality that wins the matches. He fights against The Nosonman, whom he defeats and earns a spot as the Wild Card entry.
Kalbi Bowl Ondo
In the anime, Mantaro will often sing the following song before eating his favorite dish, Kalbi Bowl:
- Japanese Version
- Karubi-don no "Ka" no Ji wa Kah-Kah-Kah (カルビ丼の「カ」の字は カッカッカ)
- Karubi-don no "Ru" no Ji wa Run-Run-Run (カルビ丼の「ル」の字は ルンルンルン)
- Karubi-don no "Bi" no Ji wa Bin-Bin-Bin (カルビ井の「ビ」の字は ビンビンビン)
- A~ Don Don (あ～ 「丼」「丼」)
- English Translation
- The "Ka" in Kalbi Bowl is for Hot-Hot-Hot
- The "Ru" in Kalbi Bowl is for Nice-Nice-Nice
- The "Bi" in Kalbi Bowl is for Strong-Strong-Strong
- Aaaaaaaahhh, Bowl-Bowl!
- English Dub Version
- With my rice I like to have some cow, cow, cow
- It tastes so very good, I don't know how, how, how
- It's my favourite form of chow, chow, chow, wow
- Oooooooowww, EAT NOW!
- Kajiba no Kuso Djikara (火事場のクソ力 Burning Inner Strength)
- Inherited from his father, it is literally a burning display of power. It is Mantaro's ability to improvise during battle despite his ignorance, last longer than a Choujin with a mere 930,000 power should, and overcome great obstacles. He also seems to be able to sense when a strong Chojin is around. Renamed The Power of Ultimate Muscle in the English dub.
- Kinniku Buster (キン肉バスター Kinniku Basutā)
- Mantaro places an opponent's neck on his shoulder and grabs their thighs. He then jumps up and lands in a sitdown position, causing damage to the neck, spine, and groin. Renamed "Butt Buster" for the first several episodes of the English dub.
- Turn Over Kinniku Buster (ターンオーバー・キン肉バスター Tānōbā Kinniku Basutā)/ Invert Kinniku Buster (English Anime) / Kinniku Buster 2.0 (English Anime)
- Mantaro grabs his opponent in a front neck-breaker hold, jumps into the air, somersaults, and then performs a standard Kinniku Buster but with the opponent's body facing in the opposite direction.
- Kinniku Driver (キン肉ドライバー Kinniku Doraibā)
- Mantaro runs up to his opponent and places his head between their legs. He then leaps up, flips the opponent upside down, places his feet on the underside of their arms, and drives them into the canvas.
- Muscle Millennium (マッスル・ミレニアム Massuru Mireniamu)
- Mantaro sends his opponent high in the air vertically, then he runs into one of the ring's ropes at a fast speed, sets himself like a slingshot, and then launches himself into his opponent's back headfirst. The front part of his opponent's body is pushed into the opposite side of the ring's ropes, which leaves noticeable marks of the ropes on the opponent's front.
- Muscle Millennium Lengths (マッスル・ミレニアム・レングス Massuru Mireniamu Rengusu)
- This modified Muscle Millenium was used originally to adapt to having only one ring rope in Mantaro's match with Hanzo. After throwing Hanzo into the air, Mantaro jumped off of the one ring rope left and flew into Hanzo's back like a normal Muscle Millenium. However, with no ropes to crash into, Mantaro tilted his body toward the ground and slammed Hanzo into the hole that he had accidentally formed with his Slaughterhouse Sawblade. The hole was just wide enough that Hanzo's head and thighs stopped the two from falling into the hole. In the anime, Mantaro angled his initial jump off of the rope to be slightly higher, so that when he was over the hole, he would be able to kick off of the rafters over the ring and launch Hanzo and himself downward with similar force as a regular Muscle Millenium. Called Muscle Millennium Crash in the English dub.
- Muscle Gravity (マッスル・G(グラヴィティ))
- Mantaro performs a standard Kinniku Buster, but right before hitting the mat he invokes the power of the Kajiba no Kuso Djikara, creating an intense increase in gravity, and flaps the opponent's body outstretched forward, causing their chin to rest on his shoulder. He then clamps their arms with his feet, causing their neck, spine, arms, and legs break and their chest to tear open upon impact.
- Kinniku Clan Special Back Drop (キン肉族スペシャルバックドロップ, Kinniku-zoku Supesharu Bakku Doroppu)
- Mantaro Air (マンタローエア Mantarō Ea)
- Mantaro performs a cartwheel and uses the momentum of the rotation to deliver a powerful kick with the side of his foot.
- Mantaro Bomb (万太郎ボム Mantarō Bom)
- This technique was used to defeat Dialbolic (Tel Tel Boy) (in the manga) and was actually used accidentally. Mantaro started out using a high angled double-arm suplex, but couldn't manage it with the amount of blood he had lost, so instead he managed to flip around Tel Tel Boy and perform a high angle tiger bomb instead, which became known as the Mantaro Bomb.
- Mantarou's Best Stretch (マンタロー一番搾り, Mantarou Ichiban Shibori)
- The Mantaro's Best Stretch or Muscle Stretch in the English dub (or ridiculously named the Stocky Locky for the anime) is a fairly simple, yet effective submission hold which was first used against Checkmate. Mantaro starts out with an Indian deathlock, which crosses the opponent's legs so that one ankle falls into the pit of the opposite knee and has the wrestler position his own leg between them, so that he faces the opposite direction and both of the opponent's legs are stuck in those positions. Next, Mantaro reaches back, as if to apply a sickle hold by simply grabbing the opponent's head. Instead of doing just that, Mantaro elevates the opponent's body by leaning forward and pulling them into a kneeling position. This technique is really more like a kneeling neck-breaker than a sickle hold, but the manner in which the two are applied are similar. It should also be noted that this move is used as a prelude to the Kinniku Buster in the match against Dead Signal and is also used as part of the Iroha Hell Tour.
- Iroha Hell Tour (イ・ロ・ハ地獄巡り, I-Ro-Ha Jigoku Meguri)
- Of the many reality-challenged moves in Kinnikuman and Kinnikuman: Nisei, this one is one of the more unbelievable ones. Mantaro created the move in order to one-up Clioneman's X-Y-Z Crash and he ultimately won with it. This technique starts with Mantaro throwing his opponent up into the air and jumping after them, crashing his head into the small of their back to form the kanji: I (seen from the two lines made by Mantaro's body and the opponent's). Then Mantaro applies his Muscle Stretch to form the kanji: Ro (seen from the slightly rounded square that the two bodies make). Lastly, Mantaro rolls backwards over his opponent while rotating his body so that his legs are draped over their shoulders and grabs their wrists, pulling them back to arch the opponent's back enough to hook his feet behind their ankles to form the kanji: Ha (seen from the upside down v formed by the opponent's legs in this hold). This entire sequence is done in mid-air and the final part is held while Mantaro drops to the ground with the opponent (called the Kid Muscle Death Drop in the English manga). This was renamed the Alphabet Soup de Loop in the English anime.
- Octopus Ink Shower (タコ墨シャワー, Tako Sumi Shawaa)
- A counter technique Mantaro used against Clioneman. When Clioneman was using his Convex Lens Body, Mantaro used this move by using octopi he found in the water to squirt ink into Clioneman and darken his lens.
- Glass Cutter Kick (グラスカッター・キック)
- Another counter technique Mantaro used against Clioneman. After using the Octopus Ink Shower, Mantaro used a back-flip kick to shatter Clioneman's lens-like body.
- Mantaro Heel Drop
- Mantaro delivers a powerful heel drop to his opponent's head.
- Muscle German
- First used against The Rigani, Mantaro basically performs a normal German Suplex, but into the corner post of the ring.
- Muscle Armor (マッスル・アーマー)
- Mantarou Gimlet (マンタロー・ギムレット)
- A counter technique Mantaro used against Lone Bone Cold. When Bone Cold used his Nasty Gimlet, Mantaro wrapped his legs around one another and spun in the opposite direction to effectively defeat his foe's move.
- Mantarou's Poop Clog Jutsu (万太郎流ウンチ停止術, Mantarou-ryuu Unchi Teishi Jutsu)
- While being flushed down Wash Ass's toilet body, Mantaro takes off his pants to clog the drain.
- Mantarou Binding Package (マンタロー小包み縛り, Mantarou Kozutsumi Shibari)
- In his fight with Wash Ass, Mantaro used this technique by taking a cut section of rope and wrapping it around Wash Ass so that his toilet lid was wrapped closed.
- M&J Shoot (M&Jシュート)
- Niku Choke Drop (肉絞め落とし, Niku Shime Otoshi)
- Stardust Savate (スターダスト・ソバット)
- A one time move used against Constellation. Mantaro shattered Buffaloman's General Stone with a kick and knocked the pieces into Constellation's face; forcing him to change into a different constellation.
- Demonic Niku Strike (魔肉の一撃, Maniku no Ichigeki)
- Mantarou Octopus (マンタローオクトパス)
- Mantarou Quebrada (マンタローケブラーダ)
- A tag technique done with Kevin Mask. While Mantaro performs a Kinniku Buster on an opponent, Kevin performs an OLAP on the same opponent.
- Muscle Docking (マッスル・ドッキング)
- A tag technique done with Chaos. Mantaro and Chaos each take an opponent. While one performs a Kinniku Buster on his foe, the other performs a Kinniku Driver on his. With the one performing the Buster descending and the one performing the Driver ascending, they "dock" when the Buster performer sits on the other's shoulders. They then drive into the canvas, affecting both opponents.
- Hercules Factory First Year No. 10 Student
- Hercules Factory Replacement Matches Champion
- Kajiba no Kuso Djikara Challenge Champion
- Chojin Olympics: The Resurrection Runner-Up (Anime: Champion)
- 1st Kinnikuman Nisei Popularity Contest (4th Place)
- 2nd Kinnikuman Nisei Popularity Contest (3rd Place)
- 3rd Kinnikuman Nisei Popularity Contest (13th Place)
- 1st Kinnikuman Nisei ~All Chojin Dai Shingeki~ Popularity Contest (2nd Place)
- 59th Successor to the Planet Kinniku Throne (Prince of Planet Kinniku)
- Hercules Factory First Year Student
- Japan Stationed Chojin - Beverly Park, Ota, Tokyo
- Team Aho
- The 8 Time Warp Chojin
- Mister Buster (ミスター・バスター)
- Kinnikuman Nisei (キン肉マンII世)
- Aniki アニキ) (Seiuchin)
- Manta (マンタ) (Rinko)
- Pigman-chan (ブタマンちゃん, Butaman-chan)
- Win/Loss Record (Singles)
- O Bone Killer (Kinniku Buster)
- O Anaconda (Kinniku Buster)
- O Kinnikuman (Kinniku Driver)
- O Tel-Tel Boy (Mantaro Bomb) [Anime: Kinniku Buster)
- O MAXman (Kinniku Buster)
- O Check Mate (Kinniku Buster)
- O Dead Signal (Kinniku Buster)
- O Clioneman (Iroha Hell Tour)
- O Scarface (Muscle Millennium)
- O The Rigany (Muscle Millennium) (Anime: Kinniku Buster)
- O Fork the Giant (Muscle Millennium)
- O Hanzou (Muscle Millennium Lengths)
- O Bone Cold (Muscle Millennium)
- O The Nosonman (Turn Over Kinniku Buster)
- O Wash Ass (Muscle Millennium)
- O Barrierfreeman (Muscle Millennium)
- O Ricardo (Muscle Millennium)
- X Kevin Mask (OLAP→ Big Ben Edge)
- O The Constellation (Incomplete Muscle Gravity)
- O Reborn Asuraman (Muscle Gravity)
- Win/Loss Record (Anime Only)
- O The Cyborg (Kinniku Buster)
- O Baron Maximillion (Kinniku Buster)
- O Baron Maximillion (Muscle Millennium)
- O Kevin Mask (Muscle Gravity)
- Win/Loss Record (Tag)
- The Young Masters (Kevin Mask)
- O The Demolitions (Muscle Gravity)
- O Beefman, Curry Lou Thesz, Unnamed Bogus Lupin (Arm Hook Double Dropkick)
- O Tenmusuman (Double Brainbuster)
- O Itto Mask (Unnamed Combo Technique)
- Δ Hell Expansions (Interference)
- O Hell Carpenters (Muscle Gravity)
- O 20 Million Powers (Muscle Evolution)
- O The Machineguns (Muscle Evolution)
- O Five Disasters (Muscle Kingdom)
- Win/Loss Record (Other)
- O Mr. Gatcha (Kid and Yone Guillotine Lariat, Three-Legged Race) (with Yoneo Sasaki)
- Win/Loss Record (V-Jump)
- O Puri-Puri Man (Kinniku Buster)
- O The Cyborg (Mantaro Neck-chancery Drop)
- O Shumokun (M&K Connection)
- O Paper Mummy
- O Check Mate (Kinniku Buster)
- O Jade (Muscle Millennium)
- O Okan (Muscle Millennium)
- O Tentacles (Kinniku Driver)
- O The Doomman (Tombstone Piledriver)
- Mantaro: Kinniku Suguru (Kinniku Clan in general), Chojin Wrestling community
- Nisei (Junior): Meat (commonly)
- Mantaro-san: Kuan, 20th Century Meat, Arenanda (second movie)
- Aniki (Brother): Seiuchin
- Manta: Rinko and her friends
- Kinnikuman's Child: Mainly villains
- Baka Aho Ouji (Stupid Idiot Prince): Meat, Gazelleman, Kevin Mask, Scarface, villains
- Kid: friends, Meat, colleagues
- Mantaro: Mother, Grandfather
- Theme Song: "Karubi-don Ondo" by Masaya Onosaka
- Favourite Food: Galbi Bowl (乫飛丼)
- Least Favourite Food: Konnyaku
- Star-Sign: Leo 
- Hobbies: Go-kon, video games, nanpa, making his own T-shirts , star-gazing 
- Fears: Snakes 
- Special Skills: Touch typing
- Catch Phrase: "One in my pants, the other in my hand!" (股間にイチモツ、手にニモツ！, Kokan ni Ichimotsu, Te ni Nimotsu!)
|Royal Kinniku Family||Kinniku Tatsunori • Kinniku Mayumi • Kinniku Sayuri • Kinniku Ataru • Kinniku Suguru • Kinniku Bibinba • Kinniku Mantaro|
|Other members||Gouriki • Salami • Phoenixman • Phoenix Shizuko • Phoenix Tarou • Powerfulman • Thief George • Soldierman • Strongman • Giara • Thomas|
|Affiliated clans||Churrasco Clan • Barbecue Clan • Horumon Clan|
|Related articles||Planet Kinniku • Kajiba no Kuso Djikara • Kinniku Castle • Golden Mask • Silver Mask • Survivor Match for the Planet Kinniku Throne • Spirit Lantern|