Stereo-Cassette King (ステカセキング) is a chojin based on an stereo-cassette player.
Stereo-Cassette King was a chojin based on a Walkman, and the weakest of Buffaloman's henchmen. He was the first of the seven evil chojin to fight Kinnikuman. He could load a cassette into himself which would give him the abilities of a certain chojin (among them Robin Mask, Ramenman, Brocken Jr., and Warsman). This led to his downfall, however, when he used an outdated cassette of Kinnikuman to finish Kin with his own moves, only to learn that despite his silliness, Suguru had greatly improved himself as a justice chojin since beginning his career. Kinnikuman then defeated him with a Kinniku Buster.
Seven years later, Ste-Casse King reappears along the rest of the Seven Akuma chojin, replacing Warsman in Russia. His opponent in the match is Turboman, which calls him an "outdated home application". On this fight, he seems to have acquired new cassettes, which he uses to dominate during half of the match. After having used Kinnikuman Zebra, Neptuneman and Mammothman cassettes, Ste-Casse decides to end it using Warsman's tape and the Palo Special. Unfortunately, Turboman has the power to "charge" his opponents' power, making them lose control of their moves. Ste-Casse King is ultimately defeated by Turboman's Complete Sting, after having lost his limbs due to overcharging.
After the Seven Devil Chojin attack a Fan-Appreciation Day Event, Warsman challenges them to a fight, and Stecasse King latches onto his head with his headphone-styled feet.  He blasts music at 100,000 phones, which breaks Warsman's eardrums and renders him deaf and unconscious.  After the Seven Devil Chojin kidnap Meat, they challenge Kinnikuman to fight; he at first avoids Stecasse King, but Stecasse King starts to play music to lure Kinniuman to him.  They have the first match.
The match takes place at Tokyo Tower, and Stecasse King confidently cleans his internal mechanisms on the side of the ring. He has Meat's torso hostage, and he enters the ring with a backpack, while he constantly tries to use his "Devil's Symphony" on Kinnikuman. Kinnikuman soon knocks him down with a horizontal chop, followed with a Boston Crab hold.  It is revealed Stecasse King has tapes of all the chojins' techniques, and he uses Warsman's techniques to gain an advantage in battle. 
He then switches to using Ramenman's techniques, and then later to Robin Mask's techniques. Stecasse finishes with his Devil's Symphony.  He blasts the music to 1,000,000 Phones, and Terryman realises that the music is coming from the radio, and the tower acts as an antenna.  The radio programme eventually stops, which allows Kinnikuman to use a Back-Drop. Stecasse King tries a new tape, but the tape is Kinnikuman's from the start of his career, and this means his skill is too low to fight. Kinnikuman then defeats him with a Kinniku Buster. 
Turboman arrives in the USSR, where he anticipates fighting Warsman, but - instead - Stecase King arrives to fight him in Warsman's place, due to Warsman still being in suspended animation.  Stecasse King jumps onto Turboman's head, where he blasts him with Hell's Symphony.  Turboman eventually retaliates by grabbing Stecasse King's legs, and breaks free with a Powerbomb.  Stecasse King swaps tapes and changes tactics, as he counters with a German Suplex, and Turboman - seeing the tape belongs to Kinnikuman - assuemes Stecasse has made the same mistake as in the past, by choosing a weak tape. It is revealed the tape, however, is based off Kinnikuman Zebra. 
Turboman is sent hurtling into a wall with an Inferno Muscle attack.  He attempts to counter with a Rolling Savate, before throwing his body at Stecasse to stop him from changing tapes, but Stecasse - using Neptuneman's tapes - protrudes spikes from his body, before using a Double Leg Suplex. When Stecasse changes tapes again, Turboman promises to crush him before he can press 'play'. Stecasse gains the upper-hand, first copying Mammothman and then Warsman. The PALO technique causes Turboman to start to glow gold. 
It is revealed that Turboman has purposely let himself be hurt over and over, so that he could store the energy from Stecasse.  He uses Earth Crush to transfer all of of his stored power into Stecasse, and Turboman's right arm and left leg are sent hurtling from his body. Stecasse strives to stand, as he attempts a Bear Claw and a Screwdriver, but - due to being so overpowered - his other arm falls off in the process. Turboman finishes with a Complete Sting technique. This completely breaks Stecasse, who falls limp and lifeless out of the ring onto the floor below. 
- Ste-Casse King jumps on the opponent's head and use his legs, which is a headphone to play a powerful song directly into their ears that can knockout a chojin like Warsman. But in order for his technique to work properly, he needs to be in a place where he can receive the signal, such as Tokyo Tower. In the battle against Kinnikuman, he accidentally plays comedian show instead of music when the music program is over. But later in series, Ste-Casse manages to overcome his weakness when he manages to use Devil's Symphony in Russian. Ste-Casse can increase the volume to make the technique so powerful that he was nearly defeat Kinnikuman despite wearing a mask that can protect sound.
- Ste-Casse King has a backpack that contain tape which has recorded a chojin's techniques and movement. By insert the tape and press the Play button on his side, Ste-casse use that chojin's techniques and movement. Also when using the chojin's tape, Ste-casse's face become similar the chojin's face or mask. But despite being powerful, Ste-casse's tape can backfire at him if he use a tape that is useless such as Kinnikuman from 1979. when is he was weak.The tape that he has was:
Warsman: Palo Special
Ste-Casse King wraps his legs around his opponent's legs and tugs on his opponents arms until they surrender and/or their arms dislocate.
Ramenman: chojin Kung Fu
Robin Mask: Tower Bridge
New chojin Complete Works
- After the match with Kinnikuman, Ste-casse has been record new data for new tape of his backpack. By insert the tape and press Play, Stecasse not only he can use that chojin's techniques.but he can also use their power and special abilities. After press Play, Stecasse can also change his body and head into that chojin's physical body such as Kinnikuman Zebra's stripes, Neptureman's vest and Mammothman's trunk and tusks, even Warsman's Bear Claws. The tape that he uses was:
Kinnikuman Zebra: Muscle Inferno
Neptureman: Double Leg Suplex, Quarrel Bomber
Mammothman: Nose Fencing, Big Tusks
Warsman: Palo Special, Screwdriver
- One of the 7 Devil chojins
- Fight Record
- Fat Pig
- The Chojin with 1,000 Bodies
- Theme Song
- Secret Cassette Transformation (Maruhi Casetto Dai Henshin) submitted by Masanori Sato
|General Devil, Satan|
|Seven Devil Chojin|
|Buffaloman, Springman, Atlantis, The Mountain, Mister Khamen, Black Hole, Stereo-Cassette King|
|Six Devil Knight|
|Asuraman, Sunshine, The Ninja, Junkman, Planetman, Sneagator|
|Omega Centauri Six Spears|
|Omegaman Aristera, Hailman, Pirateman, Gear Master, Mariquitaman, Lunaight|