I Imagine Somebody Else Fucking My Wife Everytime I Fuck Her

I fucked my wife last night .... I imagined her sisters husband was in bed with us ... I was lying there holdind my wifes hand and gazing at her face as she lay there, her eyes almost closed, her mouth slightly open, her legs spread wide apart and our brother in law between them, his arse pumping as he fucked her ....omg just omfffg