Tomoka, who lost her husband in an accident three years ago, decided to stay at a love hotel by mistake the night before her son-in-law, Tadashi's first choice university entrance exam. Coupled with the atmosphere of a love hotel, Tadashi can't control his sexual arousal for his mother-in-law who sleeps in the same bed. It seems that he desperately tries to suppress the penis that Tadashi keeps erecting, but gradually it is suppressed by the penis.