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.
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 absorb other people's stamina. He does this by first touching the target and then inhaling their strength away from them. He can use the stolen stamina to greatly increase his size and strength.