A traumatized former officer hell-bent on revenge receives an order to go undercover within the Yakuza by befriending their most frenetic member.

Shogo Kanetaka is a police officer, who suffers from trauma when his loved one was murdered. Since that horrific time, Shogo has only thought about revenge. He then receives an order to go undercover as a yakuza member. The police instructs Shogo to pick a fight with yakuza member Hideki Murooka as a stepping stone to gain entrance into the organization. The police have data that shows Shogo is matched with Hideki 98%. Meanwhile, Hideki is the son of a death-row convict. He has a physical condition, where is he always hungry and constantly eating. Also, neither her nor the yakuza can control his emotions.