Beatrice Sizebed appears in the episode "The Ring of Powers". She is a wizard princess and the heiress to the Bedfellow throne, which is the Mattress King and Queen of New York. She is originally engaged to Leonard Powers, but gets switched to Mark Lilly when Mark tries on Leonard's engagement ring.
Leonard made the biggest mistake of his life three centuries ago by proposing to Beatrice. However, he managed to "put it on ice" by literally putting her inside a block of ice. When Mark is charmed into trying on Leonard's ring, the marriage countdown begins... but with Mark as the groom instead. The ring also gives Mark the "power of influence".
Beatrice becomes an insentient zombie upon emerging from the ice block. She and Mark eventually get married. On the wedding day, Doug is under Twayne Boneraper's order to kill Callie Maggotbone since she has gone good under Mark's power of influence. Doug, instead of killing Callie, shoots at the supporting beam of the elevated viewing stand, which falls down and crushes Beatrice. Her death deactivates the rings, Callie becomes evil again and Doug no longer needs to kill her. Since Mark is in Beatrice's will, he will never need to buy a new mattress again.
- Beatrice was born in 1635 and killed in 2011.