Ever since he was young, the protagonist has been plain and never popular with women—a total virgin. One day, as he steps out of his room, he runs into Mrs. Satomi, who moved into the neighboring apartment a week ago. He finds himself strangely drawn to her, especially noticing she cleans the entrance every day without wearing a bra. The more he learns about her daily routine, the stronger his hidden feelings grow. One day, hearing mysterious moaning sounds from next door, he can no longer hold back. He climbs over the balcony wall and peeks into her room. In that instant, an unprecedented shock and excitement overwhelm him, and the story takes a bold new turn.