Ask to stay for the exam, the male student always betrays his sworn girlfriend

Yuzuru had to go to Tokyo alone to take the upcoming exam. He was allowed to stay at the house of his senior Kazuya who had graduated. Kazuya and Yuko are a couple living together. Yuzuru has been infatuated with Yuko's beautiful chest since high school, and now living with her again makes him extremely flustered and excited, unable to control himself. Yuko adds fuel to the fire by constantly wearing revealing outfits that accentuate her large chest, even asking Yuzuru to hang her lingerie out to dry. Yuzuru even witnesses Yuko and her lover making love that night... Despite this, Yuzuru tries to restrain himself and not make any mistakes.

However, the next night, when Kazuya is late due to entertaining clients and Yuko is drunk, Yuzuru has to help her to bed. He intends to leave but Yuko calls him back. "Do you want to admire my chest?" "I'll let you admire it." "You keep staring at my chest." Yuko's seduction eventually becomes too much for Yuzuru to resist. They engage in sexual activity continuously when Kazuya is not at home. Yuko gave Yuzuru three unforgettable summer days that he will never forget...