Many, many years ago when I was a naive youngster, I'd been watching quite a lot of porn and found myself turned on by shemales, so I decided to go one step further and visit one. This was before the days of easy internet searches via AW, but I found a Brazillian girl in London who looked extremely feminine. I was expecting to have a great time, but it was awful.
He/she had great curves, great boobs and a pretty face, but as soon the clothes were off and I saw the dick, things went downhill. I received oral and seemed to enjoy it, but then she put a condom on herself and sat over my face to force her dick into my mouth. I sucked for a few seconds before feeling repulsed and pushing her off. Attempted to penetrate her, but couldn't get hard enough. She then tried to shag me instead, but I was feeling so repulsive that as soon as the end of her knob touched my ass, I ran to the shower, got dressed and got the hell out.
So just a word of warning: Sometimes fantasies are best kept as just fantasies. I still watch a bit of shemale porn and get turned on, but I never want to experience it in real life again.