@ranara25 it's only natural. it's the circle of degeneracy: you get interested in the dark side, you go deeper, you find something that is too horrible, and you go back to wholesome manga.
@SveNo
He calls him Nao-shi but -shi isn't a widely enough used honorific to leave as is. Plus, the connotation is actually the same as calling your friend Mr. in English so it's actually appropriate to use it here unlike how -san might be translated as Mr. or Ms. which makes no sense because that's a standard honorific, and normal school kids don't call each other that.