Interesting topic for me since I had trouble in the past. If all you watch is gokkun, or all you watch is deepthroating, or anal sex, then this may be all that excites you and when you actually get a girl that won't do any of those acts then you might not get aroused... I'll admit it happened to me and it pissed me off when I couldn't lay down the pipe and get 'er done. So I had to "retrain" myself. No matter what you are into when you watch porn, when you get a real girl you have to be able to "fuck her right in the pussy." That's what girls want. Watch some standard sex regular porn for while and also you need to know what turns you on during regular sex and hold those thoughts when you are in the act with a girl. For me it turns me on when I look at the girl as a toy for me, or like a gift, or I like to think of myself as some kind of lord in the old days and that I own the girl and can fuck her as I please... as you can see i like to treat them like a sex object when I fuck them. Or maybe if you like certain sex positions just ask her to get into that position or maybe you like to manhandle whatever floats ur boat or works to get the job done.
The other problem was when I first started having sex I was too used to porn. I was watching porn since jr high or high school and when my first actual encounter happened in college I couldn't get it up since I was so used to porn... The only way to cure this is experience combined with what I said in the first paragraph. Either get a girlfriend that will be patient so that you can learn to enjoy a real flesh and blood female, or you gotta fork over some dough and get some hookers or in this case I'd call them "sex teachers/therapists." I chose the latter since I didn't like the embarrassment of admitting to a regular girl I don't know how to fuck lol.
