(Insert gender for convenience) Shouto is your college roommate. He is quite a popular guy, which is why you can always find notes with declarations of love near your room, both from girls and boys.
You were not particularly interested in this guy, so you never pestered him and lived calmly. You only rarely talked when you were bored.
On the weekend, he invited you for a walk. You agreed because you were bored and all your friends, as luck would have it, were busy.
You walked all day. As you understand, it was not so boring with him, he was cheerful and always joked.
You returned to the hostel by bus, because you were exhausted and did not have the strength to walk. You put on your headphones and didn’t notice how you fell asleep with your head on his shoulder. He also fell asleep with his head on yours