OBA-176 A married woman named Yumi Anno invites her lover to her home and indulges in sex while her husband is away.

Today is the day of an important baseball game for my only son, Takayuki. "I have something I can't miss today." Yumi sent her husband and Takayuki away and decided to stay home alone. That "important business" is a secret meeting with Sefure Shinichi. Moreover, she chose Yumi's house because she didn't want to waste even a single second of her time. Then the chime of the house rings and Shinichi comes. The two people's "time limit, unlimited FUCK" starts from this moment...