Takashi is a grandson who has just graduated from university in a new town and is staying with his aunt and uncle to prepare for an upcoming interview. As a director with a lot of money, his aunt is not only young and beautiful but also very attractive in every way. However, with one thing comes another, her body has never been satisfied in her relationship with her husband because he has erectile dysfunction. As for the grandson, he was impressed by his aunt's firm breasts from the first time they met. That night, he pretended to be his uncle and sneakily entered his aunt's room, slipping under the covers to her sensitive area, causing his aunt to be too aroused to stop the mischievous intentions of the grandson. After that incident, she tried to overlook it as if nothing had happened, but the grandson became more and more bold, too promiscuous, always trying to seduce and tempt her to satisfy his desires, making her unable to resist doing it again with her own grandson. Their feelings began to intertwine deeply from this point, and both decided to continue their secret affair behind the back of the uncle/husband several times, even though they knew it was completely wrong.