Ichiban Kasuga (春日 一番, Kasuga Ichiban) is the protagonist of the Yakuza/Like a Dragon series from Yakuza: Like a Dragon onward, as well as the protagonist of The Legend of Ichiban Kasuga: Part 1 in Ryu Ga Gotoku Online. He is a former member of the Arakawa Family, a Tojo Clan subsidiary. The dragonfish tattoo on his back earned him the nickname "The Rock Bottom Dragon" (どん底の龍, Donzoko no Ryū.)