Work Mates Wife

My workmate loans out his wife for men to fuck, literally.
And I've been visiting her for the past two months.
Normally I'd never get to fuck such a beautiful, horny young woman. But she's a nymphomaniac and loves older mens cock.

My work colleague lives a few minutes from me, so he texts me when he leaves early for work.
I drive to his home, walk in and within a minute his twenty four year old wife is sucking on my cock.
I've fucked her in all her holes, in many many different positions and do so every visit, which can be four mornings a week.

She especially likes me fucking her arsehole as I'm apparently more well endowed than her husband.
For his part, he'll ask me in work how my morning fuck went. He likes me to go into detail, so I try to remember everything his wife and I do in the half hour I spend in his home.

Yesterday they both asked me if I'd call round after work one evening next week, so he can watch me fuck her. I'm really tempted, but I've never had sex where another guy is present, and especially the husband.