Rikiya is a huge, tall and very muscular man.
He wears a black tank-top with jeans and sneakers, as well as a plague mask that covers his head. He also wears massive gauntlets and knuckledusters on his fists too.
Rikiya seems to require energy to move effectively, as when he charged through the gate at the beginning of the raid, he complained how it was too early for stuff to happen. After he was temporarily captured and absorbed the energy of people around him, he declared he 'felt like a new man'.
In general, it seems Rikiya enjoys absorbing energy from others, which may simply be a byproduct of his Quirk or indicate that Rikiya is normally rather lazy. He also demonstrates a slightly perverted side during his battle against Nejire Hado where he suggestively moved his hands at the idea of touching her after his Trigger worn out.
He escaped, using a Trigger on his Quirk and absorbed the vitality from the police and heros to become stronger and break the bindings and continue fighting. Himiko Toga in the form of Deku tricks the heroes into sending Rikiya crashing down to the underground tunnel where his boss is fighting. He fuses together with Overhaul, becoming a monstrous amalgam of flesh to fight Deku. After an intense battle, Eri uses her Quirk to defuse him from Overhaul and he is arrested along with the rest of the Hassaikai.
- Enhanced Strength: Even without activating his Quirk, Rikiya exhibits superhuman brawn, befitting his massive build. On two separate occasions he effortlessly burst through a wall and a locked gate, knocking several policemen into the air while doing so, and casually damaged the jamb while readying his next punch.
- Enhanced Durability: Rikiya was able to shrug off an attack from a weakened Nejire Hado.
Vitality Stealing: Rikiya's Quirk allows him to siphon away other people's stamina by inhaling their strength away from them. He can use the stolen stamina to greatly increase his own size and strength. In order to use his Quirk, Rikiya needs to be touching the target.
Metal Gloves: Rikiya wears a pair of metal gloves on his hands to augment his punches.
Trigger: Rikiya uses this drug to enhance his Quirk so he can siphon people's stamina without needing to touch the victims.
They have not been seen interacting with each other, but it can be assumed that Rikiya is just as loyal to Overhaul as much as the rest of the Eight Bullets.