A blumpkin that is given to oneself, usually while taking a shit. When you suck and/or masturbate your dick; waiting for the climax to push the turd out. Gives an extra sense of stimulation.
yo meehan, go give yourself an autoblumpkin in your momsbathroom.
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.