Who gon' stop me

The express of someone's interrogation on who could possibly stop them, used as an ironic way to say no one can.

Person 1: If we were the last people on earth and we had to reproduce to make the world continue, would you reproduce with me?
Person 2: No because that means our kids would have to reproduce with their brothers and sister-
Person 1: Who gon' stop me? If we the last people on earth, who gon' stop me?