Mad Devil Yankee

Shinya favors a rugged, workwear look built around a pale cargo shirt worn over cargo trousers, both with the cuffs turned up a touch, cinched at the waist by a belt. A strap runs diagonally across his torso, marked with a patch that reads "Devil," while his own alias is stitched along the left sleeve. He keeps his hair in an undercut and ties a bandana around his brow.

For the staged operation he disguises himself as the invented hero Papillon 800, trading his usual clothes for dark armor stamped with a large butterfly on the chest. A modest pair of wings sits at his back, and a butterfly shaped mask hides his face.

Beneath the delinquent exterior, Shinya carries genuine conviction and a heroic streak. Mumen Rider stands as his greatest role model, and he feels real shame over having been pulled into the fixed gambling scheme, viewing the whole arrangement as a stain on what heroes are supposed to represent.

Once a troublemaker, Shinya was among the crowd cheering on Mumen Rider during that hero's doomed stand against the Deep Sea King. The sight of such stubborn courage moved him to take up hero work himself. When later ordered to play a scripted role in a rigged betting operation, he refused, calling it an affront to heroes. McCoy then applied pressure of the cruelest kind: Shinya's mother was receiving special treatment at the Hero Association Hospital, and that care would be withdrawn unless he cooperated.

Cornered, Shinya took the field as the fictitious C-Class Rank 333 hero Papillon 800 and ran into Shiverhuahua. Reciting his lines from a cue card, he attacked in the belief that victory was guaranteed, only for the monster to prove vastly tougher than the script promised and beat him savagely. Bloodied and fading, he asked McCoy to tell his mother he had left town for honest work, then threw himself at the creature one last time. Saitama arrived and destroyed the dog like monster, and Shinya collapsed, waking to find Mumen Rider carrying him toward the hospital. In time it emerges that he has stepped away from hero work altogether and now earns his living as a delivery man.

As a highly ranked B-Class fighter, Shinya is presumed to be reasonably strong, though Shiverhuahua overwhelmed him with ease. His durability and endurance let him soak up repeated hits from a foe that could send him flying with one blow, and despite deep bruising and bleeding he stayed on his feet before finally passing out. In combat he relies on his fists, favoring straightforward hand to hand striking.