All performers portray adults. Still a virgin in college, I finally move into a place of my own. While greeting the neighbors, I discover that Kana, a disarmingly seductive married woman, lives next door. From that night on, masturbating to her moans through the thin wall becomes my daily routine. Days later, our conversation turns to working out. When I tell her fitness is my hobby, she says she wants to tone her body too, so I agree to train her—unaware that she will soon take control.