Yuba the Gnome
Yuba the Gnome is one of the teachers at The School For Good and Evil. He teaches Surviving Fairytaleis. In the second book, A World Without Princes, he was known as Helga the Gnome. He is a forest survival teacher, which is for Evers and Nevers.
He is friends with Merlin and helped make the gender swtching potion.
