Leaving the scene of a sexual encounter before one's partner has had a chance to clean up. (specifically/crudely: while things are stilldribbling out of things)
He was a total asshole. Pumped me full of seed and pulled a French exit quicker than you could say 'je ne sais quois.'
The act of drinking an entire bottle of wine and leaving a party with the host's wife
John brought a bottle of pink mosacto and performed a French Exit at Zach's party and now Zach and Sarah are getting a divorce. Fuck John, but not in the way Sarah did.