The act of shaving your head and then sticking the excess hair to the tip of your erect penis using the fat chicks faeces, before inserting the penis into the fat chicks unwiped ass.
Yo Jake, did you hear that Kian pulled a Dirty Kian on that fat chick at the bar last night
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"