Man, I'm having a problem with my memory these days.
The manga, from what I remember, is mainly a gender bender. The main characters are two friends, a guy and a girl. The girl is sort of a tomboy. The plot of the story flows in this direction: The girl likes the guy, but the guy doesn't see the girl as a woman. Thus the girl always steals the other girls who are about to go out with the guy. By "stealing" I mean she dresses up as a guy and makes the girls fall in love with her so that they forget about the guy.
This is all I remember...I don't think it had too many chapters, it may have been a sidestory or oneshot. I'd really like to read this again so if anyone knows what manga this is please tell me; it doesn't matter even if its just a guess.