Yusei is at a loss when his wife leaves him after a fierce marital quarrel. Unable to see Yusei in such a state, her wife's sister Serino agrees to act as her mediator. She would be relieved if Serino, who is beautiful and caring, would cooperate. While Yusei was happy that she had found an ally she could trust, Serino was intent on making Yusei relax. Eventually, the wind blows over the eugenics, which appears to have been completely washed away.