You mean "dirty sanchez"
Directly From Urban Dictionary

(What you two do on your own time is up to you, but we appreciate you guys sharing it with the rest of us)
Dirty Sanchez 9431 up, 5637 down
NO, a Dirty Sanchez is performed when a male fingers a female's ass and wipes the reminants on the female's upper lip. What you referred to below, when a male inserts his penis in a female's ass then transfers the fecal matter from his penis to the female's upper lip is the Dirty Rodruigez, the first cousin of the Dirty Sanchez. Don't feel bad though, they are commonly confused.