Responses
he's his senpai by a year so uesaka is 18. there's no way a japanese high schooler can be 13. when you enter HS in Japan u can be either 15 or 16. by the second year you're usually 17. and by the third you're normally 18 or even 19 in some cases.
I like how it tells us that Kanda is17 yet it just says the other guy is in his teens, which could mean he's 13-19