At the age of 15 days old, Frankie Stein is new to Monster High. She is the daughter of Dr. Frankenstein's monster and his bride. Frankie is very friendly and athletic, but has a clumsy streak, as her body parts tend to fly off. Her pet is a puppy named Watzit.
Draculaura is the daughter of Count Dracula, but she's a vegan vampire and does not drink blood. She is 1,600 years old. Draculaura is friendly and very sweet, and develops crushes easily. She loves fashion and is a big fan of pink and black. She can walk in the sun using a parasol, but cannot turn into a bat yet. Her pet is a bat named Count Fabulous.
Clawdeen Wolf is the daughter of the Werewolf (also known as the Wolf Man). She is 15 years old, and is covered with fur, with two piercings in each of her wolf ears. She is confident, outgoing, friendly and fashionable. Her favorite color is gold. Clawdeen has a large family, including Clawd Wolf and Howleen Wolf, and a purple pet cat named Crescent.
Lagoona Blue is the daughter of the Sea Monster, or the Creature from the Black Lagoon. She loves animals and water, and is laid-back. She carries her pet piranha Neptuna in a fishbowl (like a purse).
Cleo de Nile is the daughter of the Mummy. She is the fearleading squad captain and is considered to be a mean girl, but she does have a heart of gold that all those close to her can attest to. She has a pet snake named Hissette who is somewhat poisonous.
Deuce is the son of the gorgon, Medusa. He likes to skateboard and is interested in cooking. He wears sunglasses to prevent his turning other people to stone temporarily. One of his friends is a human named Jackson Jekyll. He is in a relationship with Cleo de Nile.
Ghoulia Yelps is the daughter of a zombie couple. She is the smartest girl at Monster High, although she only speaks "zombie" — moans and groans. She is shy and bookish, but quite thoughtful. Ghoulia has a pet owl named Sir Hoots A Lot.
Abbey Bominable is the daughter of the Yeti (better known as the Abominable Snowman). She is an exchange student from "up north" and her native language is Yetish. She sometimes has trouble understanding English slang. Abbey has a wooly mammoth for pet whom she called Shiver.
Spectra Vondergeist is the daughter of the Ghosts. She writes an anonymous gossip blog and an advice column for the Monster High student newspaper, and as such is a bit of a rumor-monger. As a ghost herself, she can float and pass through walls. Spectra has a pet ferret named Rhuen.