for a man to be cussed down in arguement by a woman or to have your Jacobs cut off.
haha, dude, you just got ripped by Holly!, she totally de-manalised you with that!
or...
oh my my god, you've got no nuts, you've been de-manalised!! unlucky.
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.