This Masha won't let any dick past her. Cyclist Stepa just stopped to sit and rest. And that bitch came on to him. How can you resist? That's how guys are - you let your chick go out for an hour, and look, someone's already screwing her in the asshole. And then she acts like a prude - her mother won't let her, only after the wedding! You've got to pull them off the first night!
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.