Okay,so. My crush,right? Even though he's the perfect thing, he does something kinda stupid. He flirts with other girls, even though he has a girlfriend. And one time, he was flirting with this one girl so much, I almost cried. And, I'm not just saying this, his ex says so too. Are any of your boys stupid flirters?
i dunno. i think flirting is ok depending on the extent of the flirting. since i know you are young, i'm not so certain that he is worth the trouble of working it through (but i suppose it's worth a try!). personally, if it bothers you a lot, get rid of him -- especially since he is a repeat offender.
[edit]
wait... maybe i misread your post. is he even your boyfriend?

No he is not my boyfriend.
Apparently my job today is to parrot . Sorry girl, I hate being a parrot but :D Oh for future reference just say the exact opposite of what you intend to say that way I can beat you to it ;) (right like that would happen :P)
Your crush is entitled to be stupid and it should not bother you. Why? He is a crush nothing more. His girlfriend should be upset with his stupidity if anybody but, certainly not a gal he is not dating.
If he isn't your boyfriend, gtfo that other girl's man. He obviously doesn't like you enough to date you. So, you're just being, like Jordan said, a bit psychotic.
Otherwise, no, my man doesn't flirt with other girls. Other girls take his joking around as flirting. Poor thing can't even flirt with me properly, lmao.
In other words: Quit being a creeper and let this poor boy be.
I smell contradiction.
Stupid things =/= perfection
He's not your boyfriend, why in the hell would you cry is he was flirting with someone else?
You need to back off until (if) his current relationship ends.
Wow, uhm, i've seen from a lot of your other topics that you're obsessed with this guy. You really need to back off, seriously, he has a girlfriend and she's not you. It's not great that he flirts with other girls but that's for his girlfriend to worry about, not you. I would be so pissed if some girl was chasing my boyfriend like you seem to be chasing him.
QFT. And I'm sorry but this board made me lol.
Sorry, but he's not your responsibility. For all you know, his flirting might be "cleared" with his gf, maybe she doesn't give a damn. Or maybe he's just naturally flirty, I've heard I am just because I am being nice to people.
I mean, me and my boyfriend love and trust each other very much. Flirting with other people occur, but it's innocent and and mostly for laughs.
But as the others have said, stay away. He's not your boyfriend and you have nothing to say whether he flirts with others or not :/