Does anybody remember shoujo where male MC already had a girlfrend but female MC wanted to...

Heroine shikkaku ??? Or strobe edge??

There's a lot like that

Neither heroine nor strobe. .
This was high school genre. I only remember that she fell in love at 1st sight, confess edycji and get rejected because małe mc had a girlfrend, but she told him that she make him fall in love with her, she was totally open with this.
Even boy's current girl know about her declaration