It's not even quite clear whether the brother helped his sister, pleasured her, or taught her. Either way, she should be grateful to him after a fuck like that. It's funny to see how he uses both his phallus and her toys to develop his sister's anal hole. It's bright and exciting, and you can see the details that are so valuable in a process like this. I wonder what he will turn her on with next time.
The sisters are totally different - one is active and energetic, and the other is quiet with glasses. And the second was afraid to have sex with a guy - even her panties were not sexy. But still even she got aroused when the guy started fucking her sister in the asshole. She licked his dick before doing it and started squeezing his balls. Just like that, the quiet girl joined in. And I hope she didn't regret it. The main thing is to start and suck in time!