Looking for story about transgender girl being cuckolded

[PieceOfCredence]

The story is about a pornstar who gets cuckolded after she allows her girlfriend to sleep with this disgusting female nerd with a much larger and uncircumsized dick. She becomes impotent as well so that she can only cum when she's with her "bull."

I have used all kinds of tags to try to find this story, but I can't.