I never got the big deal with having feelings for a highschool girl you’re close to. Really just avoid anything sex related for a couple of years and there’s nothing wrong or illegal happening. You can still go on dates and hang out (and if you get caught together rumors can go around, but that’s about as far as that can go and there’s any number of honest lies/near truths they can come up with to explain the situation without going into full detail of their mutual feelings). Explain things to the parents (or in this case mom) and get their permission under conditions and you’re golden (I mean I don’t expect that to happen, but I’m just saying). And the characters aren’t that far apart in age gap. I mean, what if there’s a situation between childhood friends where one is older by like 3 years, they can’t be restricted from still hanging out because one hit adult age first. Society can judge you based on who you choose to spend your time with, but legally as long as you aren’t assaulting or harassing or otherwise causing any emotional or psychological harm to anyone there’s nothing wrong with it (it just looks bad and is negatively viewed... which admittedly in our current society is dangerous in of itself, but that’s just because people suck and for some reason want to control every little thing you do because somehow something that doesn’t affect them or harm anyone can somehow destroy the earth). It only gets really complicated when its teacher and student (or even professor and student), but that’s because of the implications that come with the job. By which logic it’d also be more complicated to have a romantic relationship with a boss, coworker, or customer.