Nanami is a quiet, unassuming girl. One day, her boyfriend calls her to his room and asks her to try on an outfit that came in a paper bag. Nanami is delighted with the gift from him, but when she checks the contents, she finds a restraint outfit designed to completely expose her private parts. Determined to make him happy with whatever gift it is, Nanami suppresses her embarrassment, strips naked, and puts on the restraints. As the belts dig into her breasts and private parts, Nanami gradually becomes wet with joy, pleasure, and embarrassment, and as she looks at him with passionate eyes filled with desire, we bring you the love story of plain Nanami and her perverted boyfriend.