Yuka lives with her father-in-law, Toru, who retired from her husband, Tadashi's parents' house. Yuka and Toru, who work part-time while doing housework, get up early and are active every morning at 6 o'clock. Tadashi wakes up at 7 o'clock. Tohru was looking forward to seeing Yuka secretly during that hour. However, Toru who swelled greed committed Yuka one day and poured rich sperm into the back of the vagina. After that, Yuka who was vaginal cum shot in a short time until the tadashi wakes up every morning gradually awakens to pleasure.