A lazy anorexic. A slackerexic will try to eat healthy or not at all and exercize, but will just end up eating more. They'll feel guilty, but they won't do jackshit about it.
"I didn't have breakfast today, but then I ate two cheeseburgers and a brownie for lunch. I'm such a slackorexic."
av uhohtwinkie 9 december 2006