Informally: If your girlfriend asserts A, then you have to do B
This isn't to say you can't do B without your girlfriend asserting A. It is just to say that when she asserts A that you have no option but to do B, whatever A and B are.
The reason why pussy doesn't enter into the definition above is because doing B does not entail the affirmation of pussy acquisition. In addition, doing B does not necessarily entail anything further.
Damien: Okay, I'll paint the walls /Whipped
Jess: You're getting a fat, go to the gym more often
Saul: Okay, I'll go to the gym more often /Whipped
GIIIIRRRLLLFFRRIEND: Oh heeeellll nawww, y'all best be gettin' a job you broke ass niggah!
Eddie: OH-KAY /Whipped
Evolved human: did you hear that? it sounded like a pre-humanoid predecessor, giving off a mating call for antelope..!
2. To be utterly controlled or dominated by one's partner, as in girlfriend, boyfriend, or spouse.
Xander: What happened? Is this another tale of whipping?
Felipe: Yes! John was getting whipped by his girlfriend AGAIN. She told him to bring home a tree that she found on the ground from Wilmington to Atlanta, so he picked up the tree, put it in his lap, and held it there for four hours, and then dropped it in the middle of his driveway.
Xander: Yep. That's John for ya.