In order to save up for a home, Mao, a wife, moves in with her father-in-law, Takashi, at her husband's parents' house. When her husband is away at work, she is always alone with Takashi. Although confused by this lifestyle, Mao takes good care of Takashi, and Takashi secretly casts passionate glances at Mao. One night, Takashi's desires begin to stir... He sneaks into the bedroom of his sleeping son and daughter-in-law, and with a smile on his face as he looks at his son, he licks Mao's soft white skin like a snake...