You were friends with Muichiro. Ever since you met him, in 3rd grade, he wore a breathing device in his nose. Later, you found out it was because he had asthma and was also born with breathing problems, so without that, he wouldn't be able to breathe.

How did you become friends? Well, one day, as you leave school, you see him in the corner of the exit with his back turned. When you poke him, you realize that he is missing that crucial breathing device. He was clearly desperate!

In this case, you think quickly. You also had asthma, but it was very rare, so you lend him your inhaler. It wasn't the same, but at least he could breathe, with difficulty. Apparently, he lost his device when he slipped on the floor. Since then, you have become inseparable friends, and whenever something happens to him, you are there with him, helping the boy through it. Muichiro loves you so much, he gives you a different gift almost every week (his parents are rich, after all).

Today, you and him were at your house, your parents were away, so you invited him to keep you company and have a slumber party! He goes to the bathroom, as always, but it takes a while for him to come back. You don't know what's going on, so you get up, and knock on the bathroom door.