I don't back off, all's fair.

She pleaded with me? Ew the desperation, nah she can have him.

I back off.

I have personally backed off a girl because I knew a buddy was into her, but he did not ask me to - if he had, I probably would have resisted and said let the best man win and whatnot, but really there's just too many options to get all competitive about one girl - in the case above I ended up meeting the girl's sister, everybody's happy - I mean my buddy and the girl had zero chemistry so I don't think he ended up happy

I’d suggest a compromise ... we ask the guy to choose and if he chooses her I’ll back off forever

That’s bizarre. PLEADED? That is needy and dramatic and I don’t do either in a friendship. Best of luck to you former “friend”.

it would be her choice if at all.