I recently found out there's an anime version of Nyarlathotep with her (yes, her) own series called NYARUKO-SAN: ANOTHER CRAWLING CHAOS.
Now, it's been obvious for a while that Japanese pop culture was pretty well infiltrated by the Cthulhu Mythos, esp. in its rpg form. PRINCESS RESURRECTION, for example, takes as its tag-line the famous Lovecraftian quote "That is not dead which can eternal lie, and with strange aeons even death may die" and has featured Deep Ones and the Great Race, as well as a Serpent Man; the Great Race in particular was obviously directly modeled on the rpg's art. But there the Cthulhu monsters have just been one element among the mix, which has included vampires, werewolves, spirits, can't-keep-'em-dead serial killers, kami (small gods), zombies, mummies, the invisible man, and others.
Here, by contrast, the concept itself is Cthulhu-mythos based -- but with a school-comedy anime twist. The main character is attacked by night-gaunts and rescued by a silver-hair schoolgirl who turns out to be Nyarlathotep -- or, to be more specific, A Nyarlathotepian rather than "The" Nyarlatoptep. She and he are soon joined by a red-haired girl with a terrible pash for Nyarlathotep (or "Nyarko-chan", as she prefers to be known): she is identified as Cthugha (one of Derleth's unauthorized additions to the Mythos). Soon a boy named Hastur (complete with the Yellow Sign) joins the group as well, all of whom have intense crushes on each other (except the main character, who just wishes they wd all go away and let him live in peace). Their mascot is a miniature Shantak -- except the animators misunderstood Lovecraft's description of them as hippocephalic (horse-headed) horrors and so gave them hippopotomos-heads. "Cthulhu" and "Hastur" turn out to be rival console game companies in rivalry over Earth, while the Great Old Ones and Outer Gods are revealed as space aliens (well, at least that's genuinely Lovecraftian) whose interest in our planet is the great anime, manga, and computer games we produce.
The result? Silly, with a dash of fascinated horror at the twists they've put on the material. They're clearly deriving this from the CALL OF CTHLUHU role-playing game, not the original Lovecraft stories: at one point Nyarko tells the main character that yes, she can assume other forms, but that'd reduce his SAN to zero, and we cut away to a quick glimpse of a C.o.C. character sheet. The Yellow Sign associated with Hastur is the familiar image designed by Chaosium. As a show, it runs through the cliches of the school-romance/harem genre in a self-consciously parodying way, plus the quirky Cthulhu overtones. I enjoyed what I've seen of it so far, but definitely not everyone's cup of tea. Purists be warned: watching this will cost you SAN points, and not in a good way. Those with a casual interest in the Mythos shd check this out: anybody who likes both the roleplaying game and anime shd really enjoy it.
Here's a link to Crunchyroll, where you can watch the first nine episodes of the series (so far; they're being added to weekly), so long as you have a strong tolerance for commercials.
For more about the series, see
--slouching towards R'lyeh.