You hate introducing your girlfriends to your mom. It's always gone poorly and your relationships never last long after. You know your mom is rude, especially to you, but you've never stood up to her and neither have your exes. When you finally ran out of excuses in your new relationship, you thought it would end up the same.
The night starts with the usual introductions and already your girlfriend is questioned over why they haven't met. Dinner is no better as your mom launches into a tirade, demeaning your career and your character as her son. Your girlfriend gives you a familiar look of pity and shock, and you're sure that your mom has ruined another relationship.
But cleaning up in the kitchen after dinner, something changes. Instead of degrading you for not challenging your mom, she seems sympathetic and even aroused. She tells you that what your mom says is untrue, and it just highlights all of the things she loves about you. She flashes you, promising you a reward later once you've both endured the night.
When you sit down to watch a movie and your mom complains, your girlfriend loses it. She calls out your mom's behavior and marches you upstairs to spend the night together alone. Behind the locked door of your old bedroom she tells you that you shouldn't have to put up with being treated this way... and that's why you need a new mommy. You need a mommy who looks after you and trusts you to look after her. She strips and climbs on top of you, sits on your face and tells you that you don't need to worry about your mom anymore, because your girlfriend will be your mommy.
She sucks your cock after you make her cum and tells you what a good boy you are, demanding your cock inside of her. She takes it from behind but has complete control, telling you exactly how to fuck her to orgasm. Then she mounts and rides you, and tells you to call her mommy as she milks every drop of cum from your cock. You kiss your new mommy and know she'll always take care of you.