Wataru, who has a part-time job fee, is interested in the advertisement of "Mature soap's 4P course discount" and persuades his reluctant friend Akio to go to the soap together. However, two mothers appeared in the waiting room. Surprised Wataru and Akio are about to go home, and the mothers start taking off their clothes, saying that they should enjoy themselves because they have paid the money. Confused Wataru and Akio gradually get excited.