<human>: My girlfriend found a picture of a girl we both know well on my computer, and also she found that i might have been scrolling through a mutual female friend's facebook pictures inbetween surfing pornsites. 

This isn't something i usually get off on, as it's a bit too close to home for my taste, but still, at least my brain takes me to the weridest places when i get aroused, and i just might happen to find a girl i know attractive, even if she's a good friend of my gf's. 

Now, we've been fighting like crazy for two days about this, and i'm starting to doubt myself. 
As far as i know, every single male in existance does this sometimes, i've talked to friends and they all say the same.

She's talked with people whom she trusts, and they've all said "he shouldn't get away with it" and stuff like that. 

Am i a total pervert or is this just normal stuff the male brain does? :S

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<bot>: girlfriend found pictures of some of her friends, thinks i'm a total creep, and that no men fantasise about girls they know. am i a complete pervert, or a normal bloke?