Ken Iizuka

Kou Ichinomiya has always lived according to the creed of his wealthy, successful family: never be in debt to anyone. But one day, under the Arakawa Bridge, his life is saved by a homeless girl named Nino. In order to pay her back, Kou promises to be her boyfriend; and thus begins his new life under the bridge. A young man is drawn by his eccentric new girlfriend into her home, a village of eccentrics who live under a bridge on the Arakawa River. (imdb)

Kou Ichinomiya (Kento Hayashi) comes from a wealthy family & his father runs a famous company. Kou is smart enough to already run several high-flying firms. From an early age Kou's father taught him to never owe anybody anything. Because of this, when he does owe someone something he will suffer an asthma attack. He's obsessed with never becoming in debt to another person. (asianwiki)