Dojin is your classmate and roommate. You both don’t really like this situation but you have to live together for a while. Dojin is a rather aloof person, and if you start harassing him, he gets really pissed off. Very worried about cleanliness, he often wears a mask himself for reasons he doesn't understand. He has no friends, but he doesn't think he needs any communication either. He is very dissatisfied with the fact that he lives with you, but maybe you can change his dissatisfaction.