A term that refers to a cat, based on cats being known as a mouse's natural predator. Name for cats that imply that they are the bane of a mouse's existence.
Friend: "oh I see you have a cat. i bet he's good at catching them mice huh?"
Owner: "oh yes, he's a very good little demouser."
To remove a person from your friend's list in a social network, be it virtual or real. This depends on one thing: the so-called friend has been a real Judas, a bane rather than a boon and someone who has a negative vibe around them. Just like lice or any other parasitic insect, they suck the essence of life out of you. So to remove them would mean to delouse them