The transition of a relationship from the female calling all the shots to the male calling all the shots.
Pussy taming happens because originally the male desperately wants to hook up with the female and get as much of her pussy as he can. He will do whatever it takes to do so, following her every whim; this is often termed being 'pussy whipped'. After a while he becomes confident he can have sex with her whenever he wants, so no longer has to bow to her needs. However, by this stage she has become emotionally attached and actually wants to maintain the relationship, while his lower emotional involvement now gives him the upper hand. Effectively her pussy has been tamed. The term is a derivation from lion taming.
Pussy taming can also happen in lesbian relationships as the balance of power changes between partners.
Jesse: Yo, we should totally ask Gaz to come to the ball game with us.
Harvey: Waste of time man, he's too pussy whipped by that bitch Kiandra.
Jesse: No dude, not any more.
Harvey: What happened man? They broken up?
Jesse: Nah dude, he's been pussy taming that bitch. He'll come for sure.