Honestly very glad this is a fictional relationship. I know the stalking and obsession is played as a gag, but think about this a little more than a couple seconds and you’ll be creeped out. A office worker 10 years older than a high school student offers to kiss her as repayment and when rejected, becomes obsessed with her and sends her flowers, gifts, etc. daily despite her refusals. The only reason it’s ok is because the manga portrays him as absurdly handsome. Some people get restraining orders for less.
Another more minor reason is my second lead syndrome acting up again. Why introduce a character you barely develop and his only role is to fall in love with the FL he’s obviously not going to end up with? Tbh, I like his character more. It just bothers me when we all know how this is going to end, considering the main couple is already set in stone.