Takuro, a ronin student, becomes obsessed when Ichika, his childhood friend and long-time crush, moves into the apartment next door. Shy and introverted, he can't bring himself to approach her directly, so he resorts to secretly watching her every day from afar. As his voyeurism continues, his desire to know her grows stronger, pushing him to take a bold step forward. Fully expecting to be reported, he accepts her sudden and unexpected advances—only to find himself plunged into a daily routine of non-stop sex. Surprised by this sudden turn of events, Takuro gradually finds himself deeply drawn into his intense relationship with Ichika.