Yukiya Ayase is a gentle, kind hearted, and innocent university student. The only relative he has left, his cousin Tetsuo, betrays Ayase by selling him to the highest bidder in an auction with hopes of making an enormous profit to be able to pay off his debts. Somuku Kanou, a bad-tempered (though very rich) loan shark, comes to Ayase's rescue and buys Ayase for an impressive 1.2 billion. Kanou apparently knows Ayase from something that happened between them in the past, but Ayase cannot remember...