A mother named Momo visits her son Yuuta's dormitory where he has moved out due to his studies. She feels comfortable around his roommates, Naoto and Tanai, who are both good-looking young men. While she cooks dinner for them, they can't resist their desires towards her scent and charm, suggesting a game called 'King's Game'. They manipulate her words and take advantage of her body, satisfying their lust... Despite trying to convince herself that this was just a one-time mistake, she cannot stop them from continuing their pleasure.

進学で家を出た息子・裕太の下宿先に訪れた桃子。同居人の後藤と田辺が好青年で安心した桃子は、裕太がバイトでいない間、彼らに夕食を振る舞うことに。桃子の色香と流されやすさに欲望をたぎらせた彼らは「王様ゲームをしましょう」と誘い、言葉巧みに押し倒して彼女の身体を好き放題に犯し…。長らく感じていなかった快楽に抗えなくなった桃子は一度きりの過ちだと割り切ったが、一度味を占めた彼らを制止できるはずもなく…。