Grumpy Cat Porcelain Mug, Go Away GO AWAY. Feeling grumpy in the morning? Let others know with this Grumpy Cat coffee mug Sure to be a great collectible for those who love to be Grumpy Make your friends, coworkers or family smile with this Grumpy coffee mug The perfect gift for any Grumpy Cat fan, or anyone who is not of fan of mornings