These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Monster High
Alternate Character Interpretation: Is Spectra just a know-it-all gossip with nothing better to do or is her past so traumatic (and possibly guilt-ridden) that she blocked it out to the point of not actually remembering it and surrounds herself in the lives of others because of this?
The theme song to the TV specials, "We Are Monster High" by Madison Beer. The fact that it's in the same key as "New Myth ~Next Generation~" (no, really) does not help matters.
Ensemble Darkhorse: Ghoulia has been largely the fan favorite since her first appearance, which still remains. Her original doll easily sold for 4x its retail when released onto ebay. Mattel took notice of this and gave her 6 dolls in total for 2011, including the SDCC exclusive, giving her nearly as different versions as Frankie, Clawdeen & Cleo, two of which are only available in multipacks that fans have no quams about purchasing (despite that one is a repackage of 4 old dolls included with her) exclusively for her.
Clawd and Heath also had quite a following, so much that both moved up to being main characters and getting their own dolls.
Family-Unfriendly Aesop: In "I Scream, You Scream", Cleo screws off studying for a cooking show, so she has Ascended Extra Scarah Screams use her telepathy to read the recipe. Not once do any of the ghouls even comment on how the act alone is cheating.
"It's okay to be a monster". This is also combined with Broken Aesop as well. This message is meant to be the franchise's way of saying that it's okay to be you. However, some may interpret it as meaning that it's okay to hurt other people (or worsenote Especially if someone is trying to get back at somebody else because the latter did something bad to the former.) or to generally be a bad person; something that a "monster" (by human definition, anyway) might be. After all, as most people know: nobody could ever like / love a "monster"...
It also happens to a lesser extent between fans of MH versus Novi Stars. Though considering the apparent failure of the latter it seems to have died down.
Fan Nickname: "Stepford Lagoona" for her race-lifted, brainwashed form from 13 Wishes.
Fanon Discontinuity: Most fans ignore the first book series, due to being very different from the source material (it's basically a Twilight knock-off) and having a Mary SueCanon Foreigner as the protagonist and having actual monstersOut of Focus. The book series later heavily implied that Melody was a monster herself and raised without the knowledge so she could pass, but the damage had been done. Not to mention that the book series had a huge Broken Aesop. No wonder it tanked and was cancelled after 4 volumes, replaced by the Ghoulfriends series, which is actually canon.
Foe Yay: Clawdeen Wolf talks an awful lot about Cleo de Nile on her profile page.
Second season has Toralei and Cleo going at it. For the Season 2 finale, though, things are patched up for at least one scene; Toralei and her catgirls help foil the cheating Nefera de Nile does against Cleo.
Genius Bonus: When Nefera summons a miniature Cthulhu in the season two finale, it's defeated by the catgirls; cats were one of the few things Lovecraft actually liked.
Ho Yay: In the film Why Do Ghouls Fall In Love?, some students end up falling for students of the same gender when hit by Cupids arrows while Toralei was causing trouble with them, including Manny the bull and Moe the zombie. It wears off.
From Ghouls Rule. Lilith and Cleo share shades of these when they meet in the catacombs. Some shades of this is going on between Robecca and Venus.
In the first book series Lagoona and Clawdeen exchange some rather suggestive lines, and casually mention that if they can't find boyfriends they'll date each other.
The upcoming "Freaky Fusion" line which fuses two monsters together into one will probably spawn some of this. Especially since one of the fusions is Toralei and Cleo, who are listed as having Foe Yay.
Most of the male characters get some of this due to the fact that they tend to come across as non-entities.
Hoodude. Oh so much. Especially after Frights, Camera, Action! gave him a (rather forced) prominent role.
Neightan Rot due to his downright stupid character concept.
Jane Boolittle is getting this treatment for the merchandise due to multiple copies of the doll appearing all over many stores.
Iris Clops is a minor example due to having a rather bland personality and only serving as Manny's love interest.
Seasonal Rot: The first few seasons always seem to have an arc connecting episodes and more character development between the characters. In the newer seasons it is pretty much just one event after another with no connections along with any arc that was going on being completely forgotten. The movies however still seem to hold a strong plot.
In the new season it has gotten even worse. With how each new episode is pretty much designed to show off a different student in the school, the series has pretty much just downgraded to 3 minute long commercials showing off the new doll you can buy.
Shipping: Fans ship Holt with Frankie, Draculara, Operetta, or Ghoulia. Heath and Abbey too.
Racism and bigotry is bad, and you should accept those who are different from you. Considering MH's main demographic is young girls, that anvil really needs to be dropped.
Uncanny Valley: The specials are now done in CGI. In other words the CGI character models look almost exactly like the dolls, only animated. This even leads into some degree of canon discontinuity; for example, Operetta's hair is simplified in the webisodes yet totally on-model to the doll in the specials.
The CGI gets a little better as time goes on.
Unfortunate Implications: The male characters in the series seem to only exist at best as an accessory to the female leads. The guys will always argue, never get anything accomplished on their own, and they often cause the problem that the girls will easily fix with little to no effort or will be able to have superior skills to the guys on something they just picked up where the guys have been training for a long time on. Made even worse in the Scaris Movie, where the guys fly all the way out to Scaris simply because they hadn't heard from the girls for a few days and were practically suffering breakdowns without them.