what to do about my friend who has a girlfriend (and i have a boyfriend) but keeps flirting with me?

[Monochrome]

i don't really know his girlfriend that much, all 4 of us are friends. but lately my boyfriend's been busy and his girlfriend's been busy so hes been flirting with me.. i dont like him, but i think he likes me. everytime i go on facebook (i go on in the morning and night only) he says "good mornin sexy " what should i do? i love my boyfriend and i like him (as a friend) so i don't want to hurt either of them.

[MM]

Doesn't seem like he's that worried about hurting your boyfriend or his girlfriend - or, for that matter, the conflicted feelings he's causing you. Just tell him it makes you uncomfortable, and you'd appreciate it if he didn't use that kind of language out of respect for your relationship. If he's a real friend, he'll get it and cut it out.

[uyyhu]

be a good friend. stay away

[Psychologist jr]

I agree with MM up there and couldnt have phrased that any better myself. only thing i can add is when he does this comment "dislike and if my boyfriend saw this what would he think?"
intimidate him a lil you know?
scare him for the sake of your friendship and also if your bf sees it hell know you truly do care about him