My good buddy Captain Jack wrote an excellent post on Mystery's Lounge about beautiful women who say they have a boyfriend and why that doesn't matter to you as the seducer and PUA (Pick Up Artist).
Case in point, last night I made out with a college coed moonlighting as a dancer (in the club and bathroom). She also had a boyfriend, but in many cases (not all the time, but in many cases) it doesn't matter. The really attractive women almost always have boyfriends and/or hookup buddies. She mentioned it and I simply treated it as a non-issue.
What YOU have to do is either be better than the boyfriend (assuming you want a relationship with her) or reassure her that hooking up with you will have no negative repercussions (ie ASD) if you want the One Night Stand.
Whether she has a BF or not really doesn't matter.
Like many of the PUAs before me I've actually found it EASIER to close a chick with a BF (or husband).
Also, notice that WHEN she tells you communicates different things.
If she tells you very early (i.e. before you qualify her) it means:
1) You made her feel like you were hitting on her and made her a tad uncomfortable...or
2) She uses it as a standard discourager to ALL potential suitors
If she tells you in Comfort it means: You were playing potential BF game and she can only have ONE BF...therefore she is telling you to tone down the comfort and switch to more attraction and seduction based Game.
If she tells you during S1,S2,S3 it means she wanted you to know so she didn't feel like SHE deceived you.
If she tells you afterwards it means she wanted to get f-cked before you found out but now she feels like she should tell you so you don't f-ck things up for her by being clingy or by telling someone in her peer group if you see her out again.
In most cases, I just acknowledge it, act like it is no big deal and game as usual.
The fact that another PUA (neo-rio I think) stated that all HBs "sorta" have a BF is true and is why I primarily run non-BF type game because AFTER you've f-cked them it is MUCH easier to make them a GF if you want. You can just gradually suck up more and more time until she ditches the BF.
Remember, loyalty only exists among Wings, PUAs and fellow pirates (AAAAARRRRRR!!!!)
-- The Real Captain Jack Sparrow
Killing Approach Anxiety on Mystery's Lounge by Captain Jack
Grungey: Approaching Women in the Day
Anon Asian PUA: How to Directly Approach a Hot Woman
Anon Asian PUA: Black Naturals and the Shotgun Effect
OCWaterBoy: Review of Shark's Attract and Date CD