We have a few stories kinda like this, not exactly.

I would want to do this for real but have the other guy in on it and her not know!!!! A hung bull, someone we discussed becoming our real bull but she has no clue, she thinks shes teasing me and lets him get pretty far. He will know her buttons to push and even get her number and secretly (she thinks) seduces her without me and tells me about his progress and she teases me but wont tell me all what hes saying. But then he gets her to tease me again next time but she thinks shes creating a secret roleplay with him so I dont know but I know and me and him planned it so she lets him do more and more!....Etc and of course oh wait, this has me hard and Im gonna cum