SNOS-228 The beautiful delinquent girl I saved fell in love with me... and I repaid her kindness with a passionate kiss. - Riri Nanatsumori

Yoshino is an unremarkable salaryman living quietly in a suburban apartment. One day, a flashy, delinquent-looking girl named Riri moves into the apartment next door. At first, Yoshino thinks she's a troublesome neighbor and consciously avoids her, but one day, he helps Riri when she screams at a cockroach that appears in her apartment, and the distance between them quickly shrinks. "I'll do something to thank you for all the kindness you've shown me," Riri says, and comes into Yoshino's apartment, where she starts hanging out all the time. Although she acts and speaks coldly, she takes care of Yoshino and sometimes acts sweetly. And when Yoshino can no longer resist the contrast between her outward appearance and her outward behavior, Riri opens her legs for him.