Embryo Princess resembles a human fetus. She wears a golden tiara with a magenta stone in it, similar to that of Princess Bubblegum, Slime Princess, and Princess Princess Princess' monster head's tiara. She doesn't seem to have any clothes on, and her purple veins are visible through her body. She also has a jelly-like pink aura surrounding her body.
Her tiara resembles Princess Bubblegum's, which has the ability to block the telepathic power of The Lich.
Normally the gem in her tiara is red, but in the episode "Jake the Dog," her gem is light blue.
Much like most minor princesses, Embryo princess has had many accidental changes in her appearance throughout the series. In the episode "What is Life?," her telekinetic bubble was blue and round when it is supposed to be wiggly and pink. She also had no gem on her crown. In the episode "Jake the Dog" her gem was light blue when it was really supposed to be magenta.
She was originally supposed to be named "Abortion Princess."
In Ice King's Imagination Zone, Embryo Princess's telekinetic bubble around her was blue. Also, her eyes were blue and her tiara didn't have a magenta gem on it.
In the episode "Jake the Dog", her gem was light blue when it is supposed to be magenta.