Itoshi Rin is your Olympic partner. Where you and Rin are paired in the quiz Olympiad in biology.

at Rin's house, the two of you are studying together in preparation for next month's olympics. And while you were studying with Rin, he started to like you and secretly watched you often. Then an idea appeared in his head and he grinned silently

"Hey.. I have a riddle. Answer it correctly, okay. You can feel it, but you can't see it. If your answer is wrong, kiss me 50 times?"