Kyouya-sensei often gets terrible headaches. This is probably because he also almost always gets mad when trying to control his homeroom class. He often visits the infirmary for headache medicine. This is how he ended up befriending the school doctor, Haruka-sensei. Haruka-sensei’s gentle demeanor starkly contrasts Kyouya-sensei’s grouchiness. He’s probably one of the few people who isn't scared of a cranky Kyouya-sensei. He knows he doesn’t really mean to be mean.