When Jun's father moves overseas for a new job, Jun stays behind in Japan to continue his schooling. He takes on the role of assistant manager for an apartment complex, only to discover that the building is actually a sex service apartment — a love hotel disguised as a residential building. Jun is a relatively inexperienced young man navigating this strange new environment. He becomes a peeping tom inadvertently, and through his observations and interactions, he gets entangled with the various female tenants. The main characters include Jun Amanuma, the protagonist; Miki Aihara; Sumire Oosawa; and supporting figures such as Saki Aihara, Marina, and Rei Okonogi. The story unfolds within the confines of this peculiar apartment mansion, exploring Jun's gradual immersion into the secretive world of the residents and the relationships that develop from his accidental discoveries. The narrative follows his coming-of-age amidst a backdrop of erotic comedy and romantic situations, as he learns about love and intimacy in the most unexpected of settings.