Names to Run Away From Really Fast/Unpronouncable Names

A form of Names to Run Away From Really Fast: Anything really long or otherwise impossible to pronounce on the first try. H.P. Lovecraft made this his stock in trade. For example, Cthulhu, Ithaqua, Shub-Niggurath, Y'golonac (YOU FOOL! YOU'VE DOOMED US ALL!!), Nyarlathotep,Yog-Sothoth, Etc.

Remember, you should always consider the original language of the story. Something impossible to pronounce can be perfectly easy to say for someone who hears things like that for whole life. The same applies if character is supposed to be a foreigner, it might be normal for country of his origin.

Anime and Manga

 * Many of the arrancar from Bleach. Aaroniero Arruruerie, Nnoitra Jiruga, Grimmjow Jeagerjacques, Ulquiorra Schiffer, Szayel Aporro Grantz...the list goes on and on.

Comic Books

 * Mr. Mxyzptlyk
 * Dkrtzy Rrr, a living mathematical equation.

Film

 * Samir Nagheenanajar.
 * Anton Chigurh.

Literature

 * From the Star Wars Expanded Universe: Grand Admiral Mitth'raw'nuruodo, known to the galaxy as Thrawn.
 * The Forgotten Realms books have a habit of giving their dragons hideously long names.
 * Most of the Lovecraft horrors fall into this category, but the one you must always be mindful for is simple. If someone says 'Hastur, Hastur...' you have two options. You can shoot the man before he can say the third Hastur, or you can run, and never, ever look back.
 * Nothing makes a person haul ass faster than a summoned Eldritch Abomination.
 * One example of a place name like this is Zzyzx from the Fablehaven series.
 * Parodied in A Series of Unfortunate Events -- The cruel and uncaring boss of Lucky Smells Lumbermill has an apparently unpronounceable name that is never given to the reader (and all attempts by Mr Poe at pronouncing it appear completely different). He is instead called "Sir".
 * The Secrets of the Immortal Nicholas Flamel:
 * Tsagaglalal.
 * Huitzilopochtli, another name for Mars Ultor.
 * Coatlicue, the Mother of All the Gods.
 * It's a bit of a Running Gag that Machiavelli has trouble pronouncing Quetzalcoatl's name.

Live Action TV

 * Romanadvoratrelundar from Doctor Who. While her first two incarnations were OK, even travelling with the Doctor, her third incarnation was... ruthless, to say the least.

MMORPGs

 * C'thun, Yogg-Saron, named faceless ones (R'khem, Volasj, etc), and named nerubians (Tutenkash, Anub'rekhan, etc) in World of Warcraft.

Music

 * Sunn O))) (including whatever that is after the Sunn part(you just don't pronounce it)) has a song called "Big Church [Megszentségteleníthetetlenségeskedéseitekért]". anyone familiar with their music in the least knows that this church is most certainly evil.

Mythology

 * The whole Aztec pantheon. Mictlantecutli, Centzon Huitznahua, Chalchiuhtlicue...

Tabletop Games

 * Tht Whch Hs N Vwls (That Which Has No Vowels) from Munchkin Cthulhu.

Video Games

 * Avoozl.
 * Ifnkovhgroghprm.
 * Chattur'gha, Xel'lotath, and Ulyaoth of Eternal Darkness.
 * The W'rkncacnter from Marathon.
 * Chthon and Shub-Niggurath in Quake.
 * The Big Bad of the first Alone in The Dark is an undead pirate named Pregzt, and there's also a giant Sand Worm called the Chthonian, named after an H.P. Lovecraft beast, although it looks nothing like Lovecraft depicted (which was more like a squid).

Web Comics

 * K'Z'K the Voweless One from Sluggy Freelance. So much that people can't pronounce it well, and that infuriates him.
 * From Homestuck, Feferi Peixes's lusus is a monstrous, tentacled mass named Gl'bgolyb.
 * The Zoologically Dubious beasts from Rose's grimoire have these kinds of names. Nrub'yiglith stands out in particular.
 * Secret from Keychain of Creation has a name so long that she can't pronounce it without fainting in the attempt.

Web Original

 * BKCRMWDJVG of the Whateley Universe, a demon who has its own hell dimension.

Western Animation

 * Nibbler's real name, apparently due to time constraints.

Real Life

 * For those who aren't Romanians, Nicolae Ceausescu, General Secretary of the Romanian Communist Party.