I read this wayback years ago and I forgot the title and I haven't finished reading it.

What I remember is that there is this boy with glasses being bullied by his schoolmates and there's this girl who saved him and they became friends

There's a school event and there's this boyband singing and to the girl's surprise, the lead vocalist who is so cool was looking at her while singing and she thought that the guy looks familiar.

I have been searching for this manga and been asking random people about this but unfortunately, no one knows..

Nousatsu Rock Shounen
https://www.mangaupdates.com/series.html?id=4576

I thought it sounded familiar, so I started looking through my complete list. Is it this one?