One man sitting on the toilet the normal way while pooping. While a second man is sitting on the first man’s lap, facing the first man, pooping as-well. All while a third man jerking of the second man, while they are all looking at the second man’s penis.
A fluffernutter is an overly zealous or eager person.
On a pornographic set, the fluffer is charged with the responsibility of keeping an actor's penis erect without causing him to ejaculate. The fluffernutter fails at their sole job requirement when their enthusiasm triggers a "nut".