or maybe it has his sister? and maybe she died and thats why he kept his hairs long for her behalf? not everything could be romance could also be family issues
TRUE. That could also be his sister. I did think of that, too. Personally, the reason why I'm leaning more onto the trans backstory theory is mostly due to the director's monologue that stated " no hiding, no self-deprecation, no fear of others" when he was thinking about Shizuma being open about his relationship with Minato. And it just so happened that we got a glimpse of a photo of a woman that looked like the director during that specific line and then we're shown that the director's apparently a man. Also, when talking to Shizuma earlier, the director mentioned how Shizuma has supportive friends and family, and he's easily accepted by people. The way he was saying it and the look on his face seemed to indicate a troubled past with his family and friends. Not being shunned and not being accepted as trans COULD be the reason that consequently led to his current personality because if it was really him on that photo then the things I mentioned probably led to a change. He seemed like a bright person before
*(I accidentally hit reply and was not able to add this)*
MAYBE being trans is also the reason why he doesn't correct anyone when they assume he's a woman. He identifies as one.
Correction:
"BEING shunned and not being accepted as trans COULD be the reason......."
I wonder is he's trans? There was that glimpse of a picture and it seemed like he dressed up as a woman before. Maybe a relationship gone wrong because of that.