If you are a guy, that means you would be having sex with someone who used to have a penis, and then surgically turned it into a vagina. If a girl, you would be having sex with someone who surgically got a penis attached to them. Would you have sex with this person for a one night stand? How would you feel if you were in a long relationship with them beforehand, and then one day told you this. after you've already had sex? Would you be mad?