Canon Foreigner: He only appears in the 1999 series. He was added in because with Hilda and Zelda as teenagers, there was no adult guardian living in the house.
Chuck Cunningham Syndrome: He disappears in Sabrina's Secret Life with no explanation. However, one could guess that he left because by then, Hilda and Zelda were legally adults at that point, and didn't serve a purpose anymore.
Trickster Mentor: He comes off as evil and scary but always left a loophole in whatever Sabrina wished for so she could find a way to fix it when it (inevitably) goes wrong. Though he's tired of constantly being asked.