Characters

The Monster High cartoon series, doll diaries and books focus on new girl Frankie Stein and her "ghoulfriends", their boyfriends and crushes, and the teachers and staff of Monster High.

Teala
Teala is a troll character who lived under a bridge. She has only been mentioned in Toralei's Campus Stroll diary, in which she is telling the werecat about how her boyfriend has treated her.

Facebook student
The Monster High Facebook account is hosted by a mysterious student of Monster High, strongly suggested to be a girl. Very little is known about her, but she is good friends with most of the other students. It is also known that the Facebook student's parents for the longest time didn't allow her to have a pet. When on October 6, 2010, she finally was allowed to have one, she let the Facebook visitors decide and ended up with a pink male mini-dragon.

Lagoona's teacher
A teacher of whom only the voice is known, he was heard in the webisode "Parent-Creature Conference". Lagoona Blue is his best student, so much so that he personally wished to tell her parents. Since Lagoona's favorite subject at school is oceanography and no other teacher is confirmed to handle those lessons, it is possible he is the oceanography teacher.

Phantom of the Opera
As said in Holt's Basic diary, Operetta's Campus Stroll diary, and the game Ghoul Spirit, the Phantom of the Opera teaches a keyboard class.

Siren teacher
Mentioned only in Holt's Basic diary, there's a siren at Monster High who gives voice lessons.

Celebrity backgrounders
As Monster High is about teenagers, obviously it has to reserve a spot for celebrities to idolize. To fill that spot, a number of celebrity backgroundersoccasionally show up.

Candace Carver
Candace Carver is Melody's confident older sister. Though her constant optimism irritates Melody, her advice is, more often than not, extremely useful.

A huge flirt herself, Candace rarely keeps a relationship and looks at dating as more of a game than anything. She is one Billy Phaidin's best friends and gave him the idea of visibility. They started the NUDI (Normies Uncool with Discriminating Idiots) group to promote RADs.

Bekka Madden
Bekka Madden is the main antagonist on the Monster High book series. Though she seems innocent and friendly at first, but she backstabbed Melody when she found out that Jackson was a RAD. She is very discriminating against RADs, shooting out propaganda whenever she can. This hate mostly stems from the fact that Brett, her ex-boyfriend, chose Frankie Stein over her. By the third book, Melody used her newfound RAD powers to force out all her friend's true feelings. Bekka is left humiliated and friendless, increasing her hatred greatly. Between the second and thrid books she leader of the group HUNT (Humans Unite No Tolerance). In the fourth book she was mentioned once, where she transfurred to another school.

Brett Redding
Brett Redding started out as Bekka's boyfriend, but soon ended up with Frankie Stein, passing out into a coma when he saw her head fall off. He is a huge RAD supporter, and came up with the idea of a video where the monsters all poured out their feelings, but their faces would be blurred. The video was sabotauged and though he was originally accused, he cleared his name and got back together with Frankie.

Haylee
Haylee is introduced as Bekka's best friend, though seems to be more of a servant to the girl. She was tricked in 8th grade into signing an indentured servant contract and it doesn't expire until,the end of high school, thus making her Bekka's personal servant. She was tricked Haylee into signing a contract promissing her friendship and loyalty to Bekka forever. This has completely backfires. She is mainly seen following Bekka typing her life into her phone for a phone novel titled : "''Bek, and Better than ever!" ''In book three, Melody convinces Haylee to de-friend Bekka.

Sylphia Flapper
Sylphia Flapper is a dragon woman, and the new teacher of Dragon Whispering at Monster High. Extremely beautiful and fashionable, she soon become the center of attention of nearly everyone at the school. However, it soon transpires that she is using her abilities to brainwash the student body into becoming her followers and to raise an army to strike against humans. Robecca, Rochelle and Venus manage to stop her plans. She appears in the book series Ghoulfriends Forever

Miss Sue Nami
Sue Nami is a water creature, and the assistant of Headless Headmistress Bloodgood. Described as somewhat ugly with a wrestler's physique, she's in charge of keeping things shipshape at Monster High, and takes her job very seriously. She's quite humourless and goes about her tasks with maximum efficiency, often barging past students and soaking them in water. She appears in the book series Ghoulfriends Forever

Cy Clops
Cy is a Cyclops, and one of the new students staying at Monster High's dormitories. He's a shy, quiet character who likes to stay in the background, but when the school is threatened by Sylphia Flapper, he steps up to help Robecca, Rochelle and Venus save the day. He also develops a crush on Robecca Steam. He appears in the book series Ghoulfriends Forever

Rose and Blanche Van Sangre
Rose and Blanche are twin vampires from Romania, who are new students staying at Monster High dormitories. As they are gypsy vampires, they insist on sleeping in the same place no more than three nights, often sneaking into other student's rooms to sleep. They get offended if people call them identical, as they insist one twin has shinier hair than the other. They appear in the book series Ghoulfriends Forever

Three Headed Freddie
Three Headed Freddie is a boy with three heads, and one of the new students staying at Monster High's dormitories. He has a habit of blurting out his thoughts unexpectedly. Each of his heads speak at the same time, but each one speaks in a different language. He even reads multiple versions of the daily newspaper in different languages. He appears in the book series Ghoulfriends Forever

Henry Hunchback
Henry Hunchback is a boy with a severe hunchback, and one of the new students staying at Monster High's dormitories. He's a cheery, excitable guy who is a great fan and admirer of Coach Igor. He appears in the book series Ghoulfriends Forever

Garrott DuRoque
Garrott is Rochelle Goyle's boyfriend, who remains in Scaris while Rochelle goes to Monster High. They were very close to each other, and he even made a rosebush in Rochelle's honor. While he does not appear in the book itself, he is mentioned quite often by Rochelle fondly, especially when she starts to worry about why he hasn't sent her a letter...                      He is mentioned in the book series Ghoulfriends Forever and is hinted to appear in "Scaris: City of Frights".