Never say anything negative about his gf, but be a higher quality girl. Ask what he like about her, often the convo will turn to things that bother him. Beat her in those things.
If you like a guy and he has a girlfriend then you should back off and only try and be his friend.
If the boy has a girlfriend, find a guy that doesn't have a girlfriend.
wait
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He has a girlfriend. So you butt out. It's not complicated.
you use his girlfriend like a ladder and jump over him
Well, its ok for them to hang out. If you trust her, then yes, if not then go with her. Like a double date.
You shouldn't flirt with him if he has a girlfriend.
Spy on him! A wife caught a guy redhanded giving nude photos of himself to his girlfriend.
littlekid
you can tell him, or his girlfriend if you are friends with her
Yes.