To mess up completely and utterly; to screw the pooch. Comes from pornstar/influencer/philosopher Aella's 2024 birthday gangbang, where 5 of the 37 guys allowed to have intercourse with Aella came in the fluffer and missed their shot at the birthday girl. A fluffer is an assistant who keeps performers excited on pornography sets to prepare for their scene.
Johnson, if you don't get that TPS report in by end of day you're going to get shitcanned. Step it up and don't cum in the fluffer here.