Miina Wakatuki, a big-titted married woman, moves in next door to Hiroshi, a middle-aged man, and pays him a visit to greet him. She shows up strangely not wearing a bra, her breasts perky and nipples erect in an oddly seductive appearance. Though her husband is around and they seem like a happy couple, Mizuna constantly tempts Hiroshi. Unable to resist her filthy, alluring body, Hiroshi reaches his limit. The truth hidden between the couple and Mizuna's true nature are finally revealed.