Masahiko, the president of a large company, was receiving some advice from Mukai, a subcontractor. - Financial assistance to prevent bankruptcy... What Mukai proposed to Masahiko, who refused to shake his head, was the marriage of his daughter, Ai, and Masahiko's only son, Naoto. - Masahiko, who had shown interest in Ai for some time, agrees and at the same time hatches a plan. - Until the wedding, Masahiko forbids premarital sex and pursues Ai's sexual desires. - Masahiko then takes Nao and his wife on a business trip for five days and is left alone with Ai, carrying out the training plan he has been dreaming of for many years...