detrimarital sex

Sex that happens to the detriment of a marriage. Detrimarital sex can be between the partners in a marriage and has a negative effect on said marriage. Detrimarital sex could be extramarital sex that has a negative effect on a marriage.

In court at a divorce trial:
Plaintiff: Your honor, my marriage has had a lot of challenges, but there has just been way too much detrimarital sex to keep up this charade.

Mary: Beth, why aren't you talking to your husband?
Beth: Since Aaron found out that he's into scat play we only ever have detrimarital sex :(