Yuba the Gnome
Yuba the gnome is a teacher at the School for Good and Evil. He teaches Surviving Fairy Tales to the Evers and Nevers.
He is friends with Merlin. Yuba helped him make the gender-switching potion that he uses in book 2 to hide in the girl's castle, and later in the book, he uses the potion again to turn Sophie into a boy and go in the boy's castle as Fillip.
School For Good And Evil
Yuba made his debut later on in a chapter called "Bad Group" He transforms his students into illusions of creatures like Snakes, unicorns and Hobgoblins. He gets irritated when many students have failed to tell which twin creature was good or evil. He gets even more angry when it is Agatha and Sophie's turn, at the end he says that they both are breaking the rules of good and evil that even himself can't tell which of them is Sophie or Agatha. He later on unlocks every students finger glow, Agatha being the first. He teaches them basic spells as they are first years.
A world Without Princes
Yuba turned into Helga, using a potion that Merlin made. He would turn into a female in the daytime and at night he would remain a male. He was caught by the coven, and Agatha and he tried to deny it but the girls wouldn't let it go. Like all the teachers he wanted things to go back to the way they were, he lost an ingredient list for the potion. It was stolen by Evelyn. He had enough for one of the girls to last 2-3 days. He trusted them that things would go back to the way they were if Sophie and Agatha wished for each other. Later on he was thought to be dead after his home got burned by the Dean.
The Last Ever After
Yuba was found out to be alive, as he is the teacher of surviving fairy tales, at his time he decided to reunite the League Of Thirteen Reaper helped, he wanted more members but a lot of them refused.