An anime is nothing without its protagonist. No matter the genre, the main character is always the most important part of the series; without them, there's no story to tell. They set the tone and keep viewers invested with their goals, actions, and personalities. Most anime protagonists are lovable, kind, cute, or funny.

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Whatever their role, a protagonist is a genuinely good person who fans can resonate with and relate to. However, this isn't always the case. Some protagonists can be sinister, cruel, or even downright scary. Sometimes they're even the true villain of the story. Other times, they're not as evil as they seem, but terrifying all the same. Either way, these creepy anime protagonists have become iconic for striking fear into fans' hearts.

10 Yuno Gasai's Obsessive Love Is Frightening (Future Diary)

Image features Yuno Gasai from Future Diary

Future Diary has become an infamous series in anime history, all thanks to its psychotic female lead, Yuno Gasai. She's the very definition of a yandere girlfriend and a perfect mixture of cute and crazy that keeps the audience on edge.

Yuno's controversial character has made her iconic throughout anime, and she's still a hot topic to this day. While many love Yuno's obsessive nature, most fans agree that she's a terrifying force to be reckoned with and can't help but shudder when they see her.

9 Hyakkimaru Almost Loses His Humanity (Dororo)

Hyakkimaru wields sword

Dororo's protagonist is pretty scary from the start, given he's born without his body parts or skin. However, even after Hyakkimaru begins to restore his body, he remains a monstrous main character. He slowly becomes overwhelmed by his anger and hatred after witnessing so many atrocities, and it almost makes him lose his humanity.

Later into the series, Hyakkimaru loses most of his innocence and becomes cruel and brutal in his dealings with enemies. Though he manages to fight off his inner demons, Hyakkimaru is a frightening and merciless warrior throughout most of the story.

8 Ai Enma Is The Mysterious Hell Girl (Hell Girl)

Ai Enma Returns From The Grave In Hell Girl

For a horror anime, Hell Girl isn't too scary. Nevertheless, it has plenty of creepy and unsettling aspects, such as the mysterious young protagonist, Ai Enma. From her stoic demeanor to her eerie appearance, she can be pretty terrifying in looks alone. However, the scariest thing about her is her role in the story.

Ai is a spiritual entity known as the Hell Girl, and she's been tasked with targetting human souls and sending them to hell. Those longing for vengeance contact her through the Hell Correspondence website, where they request to have a target of their choice sent to hell in exchange for their own soul.

7 Ainz Ooal Gown Reigns Over The World (Overlord)

Ainz Ooal Gown casts a powerful spell in Overlord.

It's no surprise that a skeleton Dark Lord makes for a frightening anime protagonist, even more so when he's the most powerful sorcerer in the land. Overlord begins with the story's hero living out his final moments in the virtual reality game Yggdrasil, only to wake up and find himself a permanent part of the game's world.

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He takes advantage of this and quickly names himself ruler of the land, keeping his followers in line with an iron fist. While he's actually a very likable and kind character, his appearance is more than enough to make him one of the scariest protagonists to appear in recent years.

6 Tomie Is A Manipulative Woman Shrouded In Mystery (Tomie)

Image features a visual from Tomie: (From left to right) Tomie (long, black hair) is waving.

Junji Ito's works have become world-renowned for their horrific stories and creepy characters. One of his most famous is Tomie, featuring the beautiful and mysterious titular protagonist. Throughout the series, it's difficult to place who exactly Tomie is, but she appears to have a frightful power, which she uses to manipulate men who cross her path.

Despite her beauty, Tomie has a very unsettling aura about her that leaves those around her petrified with fear. She uses her manipulative nature to slowly break down others until they snap completely, taking either their own lives or hers.

5 Kaneki Ken Slowly Becomes A Monster Throughout The Series (Tokyo Ghoul)

Kaneki and his kagune

Though Tokyo Ghoul's tragic protagonist is one of the most popular characters in the series, there's no denying that he's also one of the scariest. After he becomes a one-eyed ghoul, his life completely changes forever, and he slowly transforms into an unrecognizable monster.

Ken becomes ruthless, cruel, and violent, willing to do whatever it takes to protect his way of life. His personality continues to change drastically as his outlook on the world and life itself changes. While he's still a very sympathetic character throughout, his drastic and shocking change is very frightening.

4 Alucard Is More Terrifying Than The Vampires He Hunts (Hellsing Ultimate)

Alucard the heroic vampire grinning in Hellsing.

Hellsing Ultimate's Alucard is the most powerful vampire hunter within the Hellsing Organization and their greatest weapon of all time. Though he's the protagonist, he's not exactly a hero. In fact, he's more like a villain than anything. With frightful power and no remorse for others, Alucard is often far scarier than any vampire he takes on.

Alucard's techniques are merciless and overpower any opponent he faces, making him a nightmare for supernatural beings and humans alike. Along with his frightful abilities, Alucard's grim appearance is enough to strike fear into the hearts of even the bravest of souls.

3 Light Yagami Becomes A Horrific Serial Killer (Death Note)

Light Yagami from Death Note laughing evilly.

Light Yagami is one of the most iconic killers in anime history, and his actions remain some of the most sinister of all time. The Death Note protagonist may not look like much on the outside, but he's a cunning and cruel monster on the inside.

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After discovering the Death Note by chance, Light quickly develops a chilling god complex and plays with the lives of those around him. Throughout the series, he's heartless and unfeeling, causing some of the most terrifying anime deaths fans have ever seen that rival even the scariest horror anime.

2 Lucy Comes From A Race Capable Of Killing Off Humanity (Elfen Lied)

Lucy Angry in Elfen Lied

Elfen Lied is one of the most iconic horror anime classics, and many consider it a must-watch within the genre. With its excess gore and violence, it's no surprise many find this series pretty scary. However, the most terrifying part of Elfen Lied is its protagonist. Apart from the horns on her head, Lucy looks like any other girl. However, she comes from a race of killers known as Diclonius, born with an instinct to kill and the ability to rip anything apart.

From her first appearance, Lucy is nothing short of menacing with her eerie appearance and apathetic, remorseless expression. Though viewers come to see the humanity within her as the series progresses, Lucy proves that she's capable of horrific things and shouldn't be underestimated.

1 Eren Jaeger Turns Into The True Villain Of The Story (Attack On Titan)

Eren Yeager from Attack on Titan's final season.

When fans first meet Eren Jaeger at the start of Attack on Titan, he's a young and hopeful boy who just wants to save his loved ones. However, years of pain, suffering, and war, transform him into something almost completely unrecognizable.

Eren loses hope and love for others, instead becoming a hardened and jaded man with little regard for others. Though it's completely understandable why Eren becomes this way, he essentially turns into the story's real villain and is one of the scariest characters in the series.

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