When two people are rubbing up and down in a vertical manner, chests touching while standing.
This can be done between any two people, regardless of sex. There is no horizontal movement, only vertical rubbing of the chest areas. Participants maybe clothed or not.
"Hes not even humping her. It's like mexican chestsex!"
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?"