It can sometimes be hard to scare viewers through the medium of anime, although that hasn't kept several classic horror anime titles from being produced over the years. From jump scares to outright freaky elements, horror anime stands out compared to most horror movies for trying different ways to get under both foreign and domestic audience's skin.

The 2000s saw the release of a number of creepy anime titles, with themes of trauma, abuse, murder and mystery all being part of these dark and gruesome and tales. However, as disturbing as these are, the following anime are all classics in some way thanks to their other elements, coming together to provide macabre and engrossing experiences that tantalize, taunt and titillate as much as they scare.

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Shadow Star Narutaru

Shina In Narutaru

Featuring a cute monster and an equally innocuous intro, many viewers might be led to believe that Shadow Star Narutaru is merely a kid's show in the same vein as Pokémon or Digimon. That's far from the case, however, and what initially seems like a fairly wholesome show quickly turns into an outright traumatizing one.

Adapting the Mohiro Kitoh manga, Shadow Star revolves around a young girl named Shiina who bonds with a strange star-like creature she names Hoshimaru. Others have also bonded with similar "dragons," and Shiina soon finds out that these people and their friends aren't as benign as Hoshimaru. The series begins to involve dark themes, graphic violence, abuse and even sexual assault, almost all of which is toward a young group of characters. The original manga was written by the brain behind the similarly twisted mecha anime Bokurano, so those in need of an inhuman soul-retching should look no further than this 12-episode series.

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Le Portrait de Petit Cossette

Le Portrait de Petit Cossette

Le Portrait de Petit Cossette is a 2004 OVA that subsequently received a manga adaptation. It's about a young man named Eiri Kurahashi who works at a local antique shop. His usual behavior begins to change, however, when he becomes infatuated with an image of Cossette, a girl in a painting. Seemingly trapped within the painting, the girl has a dark past and begins controlling Eiri more and more in a particularly twisted love story.

The series is filled with supernatural Gothic horror and art, perfectly encapsulating its creepy tone. Things only ramp up in terms of violence and gore, turning the series into a beautiful bloodbath.

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Monster

Tenma from Monster looking at his hands.

Monster originally aired from 2004 to 2005, combining horror with mystery and psychological thrills. The manga adaptation follows Dr. Tenma, a surgeon in an area of West Germany, whose life takes a drastic turn after one dark and stormy night. His choice of who to perform surgery on has a dramatic effect on his social standing, but things turn around for the better after a slew of mysterious local murders. Almost a decade later, Tenma has to confront the past and his role in the actions of a ruthless killer.

The series grows increasingly uncomfortable, diving deeper and deeper into just how depraved its villain and other characters are. Likewise, the cat and mouse game of the plot keeps viewers on their toes, not knowing how the story will unfold next. The series became relatively popular when it first came out, but has sadly been forgotten over the years.

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Boogiepop Phantom

The final title on the list is the early 2000s series Boogiepop Phantom. This 12-episode Madhouse production adapted a franchise of successful light novels. It involves a horrendous series of killings that occur after a huge pillar of light appears in the sky, with the various cast members all being witnesses of some sort. Most of them are high school students, many of whom begin to disappear one by one as the mythical Boogiepop, a figure representing death itself, is blamed.

The series focuses heavily on memory and perception, with some scenes being shown twice for emphasis and to see them occur from different points of view. Dramatic scenes are accentuated by symbolic music, and psychological trauma abounds. Color also plays into the symbolism, making this murderous mystery even murkier by the time it reaches its conclusion.

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