Sid Borg is a 2013-introduced and prose-only character. He is a cyborg and a staff member at Monster High. He runs the school's auto shop, which is used as a medical room for those students with mechanical parts. Sid is an old man who cares little for formalities and is always ready to help out a fellow mechanical creature.
He is a kind and helpful man who prefers informality. He wants the students to call him Sid instead of Mr. Borg.
Mr. Borg is a piston-powered old man with silver-plated limbs and metal teeth, considering he uses nails as toothpicks. He wears grease-stained overalls, the stains being a side-effect of him keeping himself well-oiled. Due to farsightedness, he sometimes wears glasses.
Robecca drops off Captain Penny at the auto shop to get his left wing oiled. She leaves him there when she remembers she has an appointment, so Mr. Borg oils the mechanical penguin himself and gives him to Cy Clops when the latter offers to take the pet to Robecca.
- Mr. Borg tells Robecca to "Call [him] Sid" when she refers to him formally. It is not elaborated if this is his full first name or not and if the latter, what Sid is short for.