Experiencing something so splendid that it's beyond mind blowing. Something so amazingly out of this world, it can only be expressed by comparing the subject to having your dick blown....off (in the best way)
Have you tried Karen's tiramisu? It is so good, it'll blowyour dick off!
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.