Ryo is temporarily staying at his aunt's home until his uncle returns from a long business trip. It is close to work, and living alone with the aunt he has always desired feels like a dream, but she is married and strictly off-limits. Unable to confess his lust, the adult nephew secretly uses her underwear to satisfy himself. One day she catches him searching for a freshly worn pair, but instead of getting angry, she seductively tells him he has been naughty for playing alone.