Arina is a college student who decided to work part-time at a nearby convenience store. There, she met Kotani and they fell in love. Just when she thought her student life would be fulfilling, Oki-san, a very incompetent person who was fired from his previous job, came to work at the store and discovered that Kotani was stealing from the store. He told Arina and threatened to report Kotani to the police unless she agreed to do as he said. To protect her lover, Arina accepted his offer and let him have sex with her. With his skills and 'big package,' Oki gradually seduced Arina. She became infatuated with Oki's penis and became indifferent to her boyfriend. Even when her boyfriend was fired and discovered, she didn't care, her focus now was on being fucked by Oki every day...