stainal
Anal sex that is messy and stains things.
Skeeter did stainal with his sister on my couch now it's ruined!
Stainal Sex
When two or more parties leave evidence of having anal sex without proper bowel evacuation resulting in an awful mess.
I met this kinky chick who never used the word no. Not wasting any time, I put all the love I had in her ass but she sent it all back. Now I have to buy a new mattress before my parents get home and find out I had Stainal Sex in their bed.