Kusetsuyo Kanojo wa Toko ni Izanau

Kiyoshi Naoto begins university after a gap year but struggles to find housing in Tokyo, leading him to move in with his older cousin, Luna. He has had a crush on her since childhood, and now she appears more mature and attractive. He often hears her at night, which unsettles him. Despite her many relationships, Luna grows closer to Naoto. As he tries to understand her intentions, other attractive women also begin to take interest in him. He finds himself entering a new phase of life surrounded by older women who seem sexually active.