Rin Miyazaki, the epitome of youthful curiosity, corners her cousin, Infinity, in their shared space. With their family nearby, she should know better, yet she can't help but explore the taboo. She reaches out, tentatively at first, then with growing confidence, she grips Infinity's most sensitive spot. Infinity tenses, trying to maintain control, but Rin's innocent yet eager touch is his undoing. He erupts, unable to resist her enticing allure, leaving Rin basking in her triumph over his inhibition.