Looking for a brother/sister web show story

[ThePrimeinator]

Hi there,
I read a story ages ago about a brother who discovers his sister has a web show and is persuaded to help her, he starts off in the chat to help up the amount of tips shes getting.

At somepoint she promised to do a show with a male costar and the brother has to do it, its a dom/sub show (sister is Dom brother is Sub), sister keeps going along with the show thinking her brother is fine and not into it but he is and cums

Any help finding this story would be great thanks!