Natsume Shima has a problem that keeps him single and alone: he is terrible in bed. Frustrated by his inability to keep a lover and stung by a recent breakup, he devises a plan to become a master of sex and shove his newfound prowess in his ex's face. His first step is to hire a male escort to help him improve his skills. However, when the escort arrives at his door, Natsume is shocked to discover that the man is no stranger: it is Kou Sawaya, his own housekeeper. What begins as a purely transactional arrangement quickly evolves into an unexpected and complicated romantic entanglement. Kou, calm and experienced, takes on the role of teacher, while Natsume struggles with his insecurities and the awkwardness of their existing domestic relationship. The story follows their developing bond, moving from a physical training regimen to genuine emotional intimacy. As lessons progress, Natsume's initial desire for revenge gives way to vulnerability, and he must decide whether to cling to past hurt or open himself to something real with Kou. The narrative arc centers on Natsume's journey from a self-conscious, vengeful mindset toward self-acceptance and honest connection, while Kou's own guarded nature is gradually revealed. The setting remains largely within Natsume's home, emphasizing the domestic closeness that grows between them. The series balances erotic tension with character-driven drama, exploring themes of intimacy, trust, and the courage to be vulnerable. It concludes with Natsume letting go of his old grudge and embracing a genuine romantic future with Kou.