One part of my journey with the wife.

Black bulls are not just fucking our white wives. Now they are fucking the husbands too. This made our marriage stronger while submitting to our black bull who we had for a couple years. He took my wifes anal virginity while I watched. And a month later took my anal virginity while my wife cheered me on and masturbated. We were told to buy a couple of black dildos and practice deep throating because our bull wanted us to suck cock better. We had to buy some butt plugs to use on each other so our asshole's got used to being violated.

Our intimacy and marriage both got stronger and better. Because our bull introduced us to more kinky sex. my wife and I would suck black cock together. We were invited to interracial gang bangs where the husbands were used to suck the black men that were fucking their wives in front of them.

A good bull will enhance a marriage not try to destroy it. That is not what swinging or MMF's are about. It is about the benefit to everyone.
Avoid bad bulls that try to insert themselves between a couple instead of bringing a couple together for new kinds of intimacy.