Considering how much they'd been drinking, I'm not surprised they had the idea to have a threesome. Especially since the mom is such a badass. Kissing your daughter in front of her boyfriend meant offering yourself up as a pussy for copulation. And the guy took advantage of that offer by banging both of them. He even shared his sperm with his mother when he came between his girlfriend's legs. Damn, that's fair!
Lucky for the guy - now he's gone from a wanker to a stallion. She, as a woman, appreciated his dignity, and as a bitch, she couldn't resist the temptation to take his pepper in her mouth. Now he would be spanking her mama every day, and she would be taking his cum in her cheek. Happy day!