Princess Monster Wife wears a red cloak while returning the princess parts she is made of. It is likely Princess Monster Wife wears the cloak because she is ashamed of her appearance due to the events of the episode. After all the princess parts are returned Princess Monster Wife's spirit seems to be embodied within the cloak temporarily. The red cloak flies back to Ice King's castle and lands on the ground, apparently losing whatever trace of Princess Monster Wife that remained. Ice King recognizes the cloak and hastily picks it up, looking distraught. Princess Monster Wife's disembodied voice says "Though my parts be scattered, I shall always be your wife," and tears start to well up in Ice King's eyes. Ice King then says "she gave away all my stuff!" in his standard lack of concern for others.
The origins and magical significance of the red cloak are unknown.