Due to work reasons, Masaki ends up staying with his aunt Reiko. He has everything but one thing that bothers him. That is Reiko's overflowing sexual desire. Every night, Masaki spends sleepless nights listening to Reiko's lewd voice as she indulges in masturbation. One day, while he is in the bath and feeling confused by her desire to enjoy the limited time she has left in her prime, Reiko suddenly comes in. While Masaki is in the bath, Reiko plays with his rock-hard cock while he is upset.