Sometimes this happens by accident in the heat of the moment, it can also be planned, and happens when you're wasted from time to time.
Walled is not the same as closeted, a wall in a closet is a closet wall, therefore no walling has happened.
example2: I walled Christina hard last night.
example2: Jeff walled me last night, I liked it.
Bro #2: "Three four lokos and a blunt can do that, my friend...and you got here via shopping cart pushed by Jeff...He wasn't happy."