After growing up in an orphanage, Mitsuru Ihara started working as a custodian at a large food producer. The pleasant, kind Ihara often visits his former home, pretending to be an important business man, not the blue-collar cleaner that he really is. But there's another, bigger secret: He is the reigning champion in an underground eating competition held at the company. In it, two contestants battle to see which can pack away more food within a time limit. The noble Ihara, with nine consecutive wins, always donates the money anonymously to his orphanage. The circumstances surrounding his victories, however, are often surprising and usually unusual.