These are the officially licensed Katamari Damacy Prince and Ball Plushies available from Fangamer ($36 for the set). They both stand around 8-inches tall and the Prince's hands and the ball's nipples have embedded magnets in them so you can make the ball actually grow with things like *eying picture* scissors and screwdrivers and darts? Wait is this a weapon?
Keep going for a shot prior to the ball rolling through a box of police evidence.
Thanks to Marcus O, who agrees you might as well roll the ball around in guns and knives then catapult over your enemy's castle wall.