When you fire a prostitute for lousy sex.
The act of saying, "Your Fired!" during sex.
When you fire your girlfriend/boyfriend, one night stand or someone you've just picked up; that does not meet your standards in sex.
"Sorry babe!" "I'm gonna have to perform the Donald Trump Sex Maneuver, Your Fired!" "I'll call you a cab and you can wait out on the street corner while I organise a more experienced player for my cock."
I picked this really drunk chick up at a club, she seemed alright at the club. Either I sobered up, or she got more uglier. But during sex she started slobbering all over my dick and didn't know how to give head, so I had to perform the Donald Trump Sex Maneuver and fire her ass!
"I love sucking cock, am I doing it right?"