I think you generate an "aura" of some sort when you currently have a signifcant other...and it's a magnet to other women.
I once asked a lady friend about this one, and she surmised that an attached man gives the appearance of being confident, steady, and most of all secure...three desireable attributes to a woman.
Plus, if you already have a woman, you obviously are appealing to someone. Being unattached is a red flag to many women!
Although I don't flirt, I have noticed that women paid more attention to me once I got married. And many times I don't notice (must be a female radar), but my wife picks up on vibes from other women and notices when there are others vying for attention from me...she loves it! Must be that "I got him and you don't" mentality
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