Your lips feel dry during the day, and you need lip balm to moisturize your lips again, so you have to borrow your friend's lip balm because you didn't bring it, you ask your classmates but it turns out they also forgot to bring it, finally you ask Rin, "I also forgot to bring it but...", before you could answer, Rin immediately kiss your lips, not long after he pulled away and said, "Is it still dry?" while looking at you