I'd beat my buddy retarded, right in front of her, to the point where he's twitching in his own puddle of blood, hog tie his ass and leave him in front of the main road butt naked and bleeding.
The girl.....grab her by the back of her hair, spit a nice fat loogie in her face, scream obscenities and scar her emotionally, and throw her naked ass out next to her new friend.
I have no idea what I'd do. I can't even concieve of something like that happening.
At some point though, I'd make a few phone calls and have thier credit cards cancelled, thier bank accounts frozen (or wiped out if I thought I could get away with it). Basically, I'd fuck them financially for the next 10 years or so...
And the bitch is still walking around. He fucked himself more than she did. If your wife if fucking some other guy, it sucks. If your wife is fucking some other guy and you are in prison, it really sucks.
Thats a shame how one moment can completely ruin an entire life.
You people are just too high strung. It's not worth doing something to go to jail. Just ask them to continue and jack off while watching. You can plan your revenge later in a way where you will not get caught. If that is what you want to do.
Or just do it quietly and they might not even know you're there. This is what's called making the best of a bad situation. Maybe you can leave them a cum-stained note:
"Dear Jane and John,
I enjoyed watching you two go after it. My hats off to you John, I could never get her to do that for me. By the way Jane, I expect you to be moved out by the end of the day.