Shanested is a compound word "Shane + Waisted". Originating from the early 2000's.
Shanested is when someone is to waisted to be of any use. The only good that he can do is make others laugh and make a mess that they will inherently have to clean up.
Loads of stiff cocked gentlemen ejaculating at the same time most commonly observed at an orgy or a group of teenagers gathering to watch filth smug whilst skiving school.
Lets all skive and go round garys drum,watch filth and have a spunkfest.