The Cat-Collar Charm

Harry, invisibly creeping around after curfew to take a bath with his golden egg, never expected that he would wake up the next morning in the hospital wing with a charmed pet collar round his neck... But Moody had always been trigger-happy, and when Snape found him hexed into a staircase the man wasn't exactly pleased. Will Harry ever get him to take the charm off? 3 chapter fic.