try to sweet talk her and talk bad stuff about the other guy
Then she has to choose you or her boyfriend.
Does the girl know you like her? How long have you an and your boyfriend been together? And are you asking what should you do?
If he is her boyfriend, hopefully, she would like him.
Try an show her how cool you are compared to her boyfriend
Treat her better than her boyfriend does.
Wait till she doesn't have a boyfriend or move on
You get beat up
It means that they like you more then they like there boyfriend
Find a way to impress her.
fight the other kid and take the girl
you make a girl jealous and the girl will hate her boyfriend and follow you as her boyfriend and listen to that song Justin bieber one time
Move on, she's taken.