Wolfman is a Japanese Sumo Chojin who once held the title of Chojin Sumo Yokozuna, but later switched to Chojin Wrestling. He trains his muscles vigorously and boasts of his Beautiful Muscles of Steel (鋼の肉体美 Hagane no Nikutai-bi), muscles that exceed Kinnikuman's. At first he despises Kinnikuman and calls him Zeinikuman (ゼイ肉マン, Flabbyman), but after losing to him in a Sumo match he begins to respect his abilities. From then on he appears as an Idol Chojin and fights against the Akuma Chojin.
With the 21st Chojin Olympics final preliminary and his fight with Springman, Wolfman often ends up facing rather plain opponents in one-sided fights. He becomes the cannon fodder, or jobber, of the Justice Chojin (quickly and easily defeated in order to show off how powerful the villains are), dying and returning to life three times throughout the series. Despite the poor treatment of his character, Wolfman's speciality in Japan's national sport of Sumo has garnered him plenty of fans.
Wolfman is an entrant to the 21st Chojin Olympics. 
He first appears on television, where he challenges and provokes Kinnikuman, as they are both representatives of Japan.  Wolfman continues to taunt him throughout the preliminary events.  At the third preliminary event, Wolfman slips on a banana peal and comes almost last place, so that he barely enters the top-50 that are able to proceed to the last preliminary event.  Due to Terryman being disqualified, he is able to continue. 
The final preliminary event is a ten-lap race.  Wolfman knocks Kinnikuman off a bridge, at which point The Fishers knock him off in turn.  They decide to call a truce and take on the remaining opponents; together they knock out the Fishers, before turning their counters upside-down from "9" to "6", so that they can convince others to let them pass out of pity. Due to a spill from Oilman, the last chojin fall down, and both men are able to pass through the finishing line and land a place in the main tournament. 
The first match is against Cubeman, where they begin by staring each other down before a huge crowd.  Wolfman proceeds to leave a series of slaps to all of Cubeman's square parts, which causes them to swell and extend; the red sides are blood blisters, the yellow sides are pus, and the blue sides are bruises. Wolfman then uses a Double Crush, before tossing Cubeman out of the ring. He bounces like a ball, until an elderly person pops him with an umbrella, which causes him to explode and die. 
The semi-finals match takes place in Kuramae Public Arena, where Meat Alexandria acts as a guest commentator.  Four people surround the ring, while Kinnikuman is required to wear a fundashi. The ring is flipped over to reveal a sumo circle, and Kinnikuman starts with a Kinniku-Sumo Kick. He attempts a brain-buster, but Wolfman evades the attack. Wolfman tries to throw Kinnikuman out of the circle, as per sumo rules, but Kinnikuman holds onto him to stop being thrown. 
Wolfman delivers a Rubiks Cube Slap to Kinnikuman's face.  He manages to toss Kinnikuman out of the circle, but Mayumi Kinniku bursts the swollen blisters of his head and Kinnikuman floats back into the circle.  They grab each other's belts, where Kinnikuman is nearly thrown again, and he survives again an underarm throw. Wolfman tries to crush Kinnikuman into submission, but he pushes back. Wolfman distracts him by claiming his penis is visible through his fundashi, before throwing Kinnikuman down against the ring. 
Just as he is about to be declared the winner, they realise Wolfman is fully outside of the ring. Kinnikuman has used a suplex to throw him, and he has touched ground outside of the circle first, which disqualifies him from continuing in the tournament. 
During the celebrations for the 21st Chojin Olympics: The Big Fight, the Seven Akuma Chojin are accidentally freed by Kinnikuman.  They kidnap Alexandria Meat during the festivities, and each take a body part, and declare that Kinnikuman must defeat each of them to retrieve a part and bring Meat back to life.  When Kinnikuman beats Black Hole, he cannot fight any longer and the Justice Chojin decide to fight on his behalf.  The remaining Seven Devil Chojin - and justice chojin - match up to find their opponents, and Springman is matched with Wolfman. 
He starts strong in the match, drawing blood from Springman, at Tottori Sand Dunes.  Due to Springman being able to bend his body, he is able to limit the effect of the blows and absorb the impact of the Palm Punches. Wolfman attempts a Body Slam, but Springman bounces around, and - after a series of attempted Body Slams - the ring hardens like steel. Springman jumps out of the ring, creating a staircase out of some nearby rocks, and use his Devil Tomboy attack. He squeezes hard enough to kill Wolfman. 
Wolfman attends a chojin physical and fitness day. 
After having his power level halved by the new Evil Chojin, he is placed in a life-support bubble in order to maintain his strength, along with his friends.  After Kinnikuman is killed in battle, Wolfman breaks free from his life-support bubble, and offers up his life-force so that Kinnikuman can live again.  He reaches inside his chest and pulls out his life-force in a bloody display. Before he dies, he has Geronimo cut of his danbatsushiki as a symbol of his friendship for Kinnikuman. 
He and Geronimo are later revived by the Perfect Mask. 
Wolfman meets Kinnikuman with their friends. 
They go to Korakuen Stadium, where they discuss the upcoming Universal Tag Tournament. Wolfman announces that he has teamed up with Brocken Jr..  They make their entrance to the tournament, proving a popular team with the crowds.  They are announced as official participants in the tournament with the tag name Most Dangerous Combo.  After navigating a maze to their ring, which randomly pairs tag-teams in the first round, they are matched against the 20 Million Powers. 
The gong for their match sounds.  Screw Kid and Kendaman break onto the ring, and Brocken Jr. tries to confront them, only to be struck across the head by Kendaman. Wolfman believes that the fact Kendaman has no eyes means that he cannot see, and so he and Brocken throw him out of the ring together, only for him to use his ball to return to the ring and explain he can see. Screw Kid then attacks.  He drives into both of them with his feet, while Kendaman joins him in using a Hell Screwdriver. 
This knocks Wolfman out and he loses his match. 
Wolfman is seen again when he and Brocken help Kinnikuman and Kinnikuman Great fight off reporters trying to get a picture of an unmasked Robin Mask.  After that, he is referred to as being dead and his soul shows up with other fallen comrades to help Kinnikuman during the fight with the Hell Missionaries. 
Without any explanation, Wolfman comes back to life and moves to Hawaii, where he has a successful career as a make-up wrestler. But, when Neptuneman sends out his message to all Justice Chojin in the world to come to Osaka and support Kinnikuman during his fight with Kinnikuman Super Phoenix, he and Jesse Maivia head for the airport together. They both show up (with Terryman and Ramenman) in time to stop the Evil Gods from attacking Super Phoenix's mother.
After the Survivor Match has passed, Wolfman has decided to retire from sumo wrestling because his tendon can't be repaired at all. His doctor notes that the tendon in the left leg went past the limit for surgeries and suggests that Wolfman should become a stable master. 
During the retirement ceremony, his friends and family all take a shot at cutting Wolfman's topknot. Cubeman even shows some respect towards the man who defeated him in the 21st Chojin Olympics. Meat cries because Wolfman is the second friend to retire. Geronimo recalls the time he had to cut Wolfman's topknot during the Golden Mask arc and says that this is his second time doing this. Geronimo also praises Wolfman and calls him an unsung hero. Kani Base screws up the haircut ritual, but Coyoteman slaps him and ends the ritual with a grand recovery. Mayumi hands Wolfman a trophy commemorating his service as a Chojin Sumo Wrestler. 
Black Ship interrupts the retirement ceremony, while carrying a battered Canadianman and Specialman . Meat tries to defend Wolfman, but he gets beaten up by Black Ship. Enraged by Black Ship, Wolfman challenges him to one last sumo match. Before the match begins, Geronimo tosses Wolfman's top knot back at him, giving him the strength to take on the American sumo wrestler. Despite having the advantage during the match, Black Ship loses to Wolfman because of a combination of Wolfman's Friendship Power and the Gasshō Hineri. 
In Kinnikuman Nisei, Wolfman has gained some weight and become a teacher at the Hercules Factory. He appeared at ringside along with Buffaloman and Jesse Maivia during Kinniku Mantaro's fight with Scarface but has yet to play an important role.
- Wolfman repeatedly slaps his opponent's face until it swells up to look like a Rubik's Cube (ironically first used on Cubeman, whose face looks like a Rubik's Cube already).
Wolfman Slap (ウルフマン張り手, Urufuman Harite)
Gasshō Hineri (合掌ひねり)
- Wolfman's most well known finishing move. He flings the opponent into the air either by their head or by their neck.
- He claps his hand in front of his enemy's face to disorient them.
Body Slam (ボディスラム)
- Wolfman lifts his opponent and slams them into the ground.
Izori Throw (居反り投げ, Izori Nage)
- Wolfman dives towards his opponents' leg, grabs it and pulls them up.
Shiranui Unryū Nage (不知火・雲竜投げ)
Speech & Quotes
He uses phrases like Dosuko~i! (どすこーい！) and Gottan desu! (ごっつぁんです！)
Win/Loss Record (Singles)
- O Cubeman (Rubik's Cube Twist→ Gasshō Hineri)
- X Kinnikuman (Kannuki Suplex)
- X Springman (Devil Slinky)
- O God of Brute Strength (Izori Nage)
- X Kinnikuman (Ring Out)
- O Black Ship (Gasshō Hineri)
- O Lunaight (Shiranui - Unryuu Nage)
- X Clioneman (???)
Win/Loss Record (Tag)
Win/Loss Record (Anime Only)
- O Harigorasu (Abise Taoshi)
- X Black Sumoman (Body Splash)
- O Black Sumo (Gasshō Hineri)
- O Haniwa Satan (Gasshō Hineri)
- Δ Haniwa Satan (Rubik's Cube Twist)
- O Hydra Sumo
- Δ The Sanzokun (Body Slam) (Tag Match with Brocken Jr.)
- X Terryman (Popularity Contest)
- Theme Song: "Dohyō Hero (土俵の英雄, Dohyō no Eiyū)" by Akira Kushida
- Wolfman was modelled after popular rikishi Chiyonofuji Mitsug,"Wolf" being Chiyonofuji's nickname
- In the anime he is renamed Rikishiman
- He is renamed Sosumi in the Ultimate Muscle English dub.