Wonder if Jouji's homosexual. Could explain a bunch, and fit the story's themes. He doesn't want to show his emotions, perhaps because he's afraid of being rejected and ridiculed in a macho sport environment. His family being "normal" (except for him) and there being "no reason" for him to be the way he is, perhaps because there's no reason he's gay, he just is, and his "normal" family couldn't accept that. This manga's theme rests on bringing sports into a more progressive future, from hazing, ageism and hierarchy to inclusion and involvement. Homophobia to acceptance could be another aspect of that. Just speculation, mind.