The obese woman was a complete slut

She was always there for him and now that he’s grown, she’s not going to stop being there. Once you bring a person into the world, your own world changes forever, and you will never stop being a mother. It’s in this context that she can understand that, when her son wants to fuck, she offers her pussy so he can cum. First, she spreads her legs as a sign that he can stick it in, something he does very quickly, and after a good while of fucking his mom, he then leaves his load of semen inside her. This makes the old lady very happy because she knows he will always need her.