All of the aboveIf they are married, it is preferred. They are married with an understanding they are exclusive. It’s the aspect that the wife wants other man to fuck her in front of the husband is the satisfactory aspect.
Some people are turned on by the aspect of the wife being used, some want their wife satisfied, others like the semen aspect of it.
I’m not a cuck. So can’t say what excites them.
Single girls are no different than a ONS on Tinder.
Haven't licked wifeys creampie yet, but kissed her efter she sucked.