You don't have to watch horror anime to have nightmares. Sometimes, watching some of the main characters in dark anime will give you a sleepless night.

But a dark character doesn't necessarily have to be evil or manipulative. They can be insane or commit acts that make you question your sanity. They can be twisted in some way, or they can be good characters turned evil.

Here we've compiled the top 15 dark anime characters. Before you dive in, get ready for a thrilling ride and put on your spoiler-free glasses.

1. Madara Uchiha (Naruto Shippuden)

Very few will disagree with this. UchihaMadara Naruto is one of the darkest villains in anime. Naruto fans have a love-hate relationship with this character. They love him for his fighting skill, calculating mind, and arrogance. They hate him for his cruel and manipulative nature.

Madara's goal of achieving peace is righteous, and no one can refute that. His methods are questionable and blunt.

He manipulates all the events that led to Rin's kidnapping. Then Obito watches her die at the hands of his best friend, Kakashi. Madara orchestrated all of this to break Obito's naiveté and make him easy to control. He also placed a forbidden curse on Obito's heart so he could not defy him.

Madara's twisted mindset stemmed from growing up in war and losing his family one by one. The final nail in the coffin was losing what remained of his brother, Izuna. This caused him to lose hope in humanity. So he chose to follow the path of darkness and evil.

2. Eren Yaegar (Attack on Titan)

In the beginning, Eren was a talkative, short-tempered boy driven by revenge. He had only one wish: to avenge his mother and free the world from the Titans.

However, by the beginning of the fourth season, Eren had completely changed. He was no longer the naive and kind boy he once was. Now he was calmer and much more determined. So much so that he killed over 80% of the world's population to achieve his goal.

Eren played the role of a necessary evil, so Eldia and Marley joined forces to kill him. He even tricked his friends into thinking they wouldn't hesitate to become his enemies. And his plan was a success.

3. Sosuke Aizen (Bleach)

Sosuke Aizen is a very strong, very handsome, and very dark villain by villain standards. Furthermore, his calm nature and brilliant mind make him one of the darkest characters in the anime.

Sosuke's ambition was to kill the Soul King and stand tall over everyone. To achieve his goal, he did many dark things.

He deceived everyone in Soul Society for years without revealing his true intentions. Everyone except himself was a pawn. No one realized he faked his death using Kyoka Suigetsu. And impaling Momo, his second-in-command and greatest admirer, without remorse was just the tip of the iceberg of what was to come.

4. Shogo Makishima (Psycho-Pass)

Shogo claims to be on humanity's side. He loves them, or their darker sides. So he wants to free society from the control of the Sybil System, which is turning people into mindless machines.

Shogo has no qualms about using forceful measures. He will kill anyone who gets in the way of his objective, whether it's himself or through subordinates. His unparalleled charisma and calculating mind allow him to manipulate people into doing his bidding.

He used Akane's best friend, Yuki, to lure Kogami into a trap, ultimately killing her in front of Akane when she failed the test.

5. Light Yagami (Death Note)

Light starts out as a normal, bored high school student. He receives the Death Note thanks to his encounter with Ryuk, a Shinigami, and this changes him for the worse.

At first, Light wanted to make good use of the Death Note. He killed people who were evil and deserved to die. But soon, contaminated by his newfound power, he declares the world rotten. And he must reshape it by killing evil and unjust people.

Light is a villain who shows us how a person can become intoxicated with power and ruin himself. Even so, he remains one of the most popular dark anime characters.

6. Mahito (Jujutsu Kaisen)

Mahito is a cruel and sadistic cursed spirit born of people's hatred for one another. He believes humanity must be eradicated and that cursed spirits should rule the world instead of humans. For this cause, he would do anything.

Due to the nature of his birth, Mahito is extremely skilled at understanding and manipulating humans. He exploits their insecurities to make them do his bidding.

That's how he convinced Junpei to become a sorcerer. Junpei didn't realize until the end that he was being manipulated as he died in tears at Itadory's feet.

Mahito finds joy in playing with human emotions and seeing them suffer. Perhaps that's why he's a dark character hated by all.

7. Donquixote Doflamingo (One Piece)

Donquixote Doflamingo is the opposite of someone you'd expect to be dark. Or at least his flamboyant appearance would suggest so. However, his cruel and ruthless nature makes him a character worthy of this list.

Doflamingo has an arrogant and sadistic nature stemming from his celestial dragon lineage. He killed his own father when he was only ten years old and later his brother, without remorse.

If that weren't enough, he controlled the king of the Dressrosa kingdom, King Riku, using the Devil Fruit. He then drove him mad, killing everyone in sight. When all seemed lost and everyone began to despair, Doflamingo made a heroic entrance to stop the mad king. The people accepted Doflamingo as their new king without knowing anything.

Worst of all, everyone who challenged him was turned into toys. Talk about dark.

8. Gaku Yashiro (Erased)

Sometimes you'll see characters that everyone hates. Gaku definitely falls into that category.

It's reasonable, given that he's a sadistic and psychotic person who enjoys killing. Initially introduced as a kind teacher at Satoru's elementary school, he's later revealed to be the perpetrator of all the murders in the series.

He attempts to drown Satoru after being discovered, which resulted in Satoru being in a coma for 15 years.

The source of his desire to kill began in childhood, when he tried to drown his pet hamsters. He saw a hamster standing over the dead, with spider webs above its head. Then, as an adult, he began seeing those spider webs above the heads of specific children and felt compelled to kill them.

Killing children and getting pleasure from it? Now that's dark.

9. Shiro (Deadman Wonderland)

You can't help but feel sorry for Shiro as a character, even though she's done many terrible things. She was experimented on to become the first dead man, which caused her body to deteriorate and fall apart frequently.

Shiro's nanomachine experiments left her with unforgettable trauma. Trying to cope with the unbearable pain, her second personality, called Wretched Egg or Red Man, was born.

The Wretched Egg caused a natural disaster as a form of suicide. However, she failed.

You might want to sympathize with Shiro, but that doesn't change the fact that she's one of the best dark anime characters of all time.

10. Alucard (Hellsing)

By nature, Alucard is a sadistic and cruel person. He loves to torture and humiliate his opponent in a fight while despising them. Each of his fights is bloody, earning his place on this list.

Alucard is essentially an immortal vampire. Therefore, he doesn't care about his well-being in a fight. In fact, he often uses himself as bait to lure his opponents into lowering their guard. Alucard wields two large-caliber guns as weapons. But to achieve victory, he won't hesitate to use his fangs to tear through his enemy's flesh.

Fulfilling the mission entrusted to him by Integra is Alucard's first priority. Everything else is irrelevant, whether it's killing his opponents with a smile or leaving them humiliated.

11. Shou Tucker (Fullmetal Alchemist)

Shou only appeared in one episode, but he is definitely one of the most vile and dark characters in the anime.

At first, he's seen as soft-spoken, well-mannered, and kind. But in reality, Shou is selfish, vile, and manipulative. Advancing his research and delivering results appropriate for an alchemist is his only goal.

To achieve this, he uses his own wife and 5-year-old daughter as sacrifices. Worst of all, after his actions were discovered, he showed no remorse.

12. Griffith (Berserk)

A handsome face, handsome enough to be mistaken for a girl. Griffith will likely go down in anime history as one of the darkest characters.

He's a narcissist who believes himself superior to everyone else. That's why he didn't mind sacrificing others to achieve his goals. However, knowing Guts changes everything. Your thought process and even your lifelong goal of becoming the ruler of a kingdom.

Then, Griffith began to hate him, so much so that he chose the path of becoming a demon and desecrating Casca in front of him.

13. Keyaru (Redo Of Healer)

Redo of the Healer is definitely an underrated anime. But the darkness of Keyaru, the protagonist, cannot be underestimated. He's a cruel and twisted hero turned villain—who wants revenge on everyone who wronged him.

Not that you can blame him. Imagine being summoned to another world only to be betrayed, imprisoned, drugged, and molested to the point of insanity. By a stroke of luck, he manages to regain his sanity and return to the time he was summoned to using the philosopher's stone.

He doesn't care about his methods, as long as he can exact his revenge. In one instance, he exacts his revenge by contaminating and brainwashing the main perpetrator into loving him. And that's not even the darkest part. He transforms the knight captain responsible for his older sister Anna's death into a woman. Then he orders his brainwashed subordinates to rape him.

14. Yuno Gasai (Future Diary)

At first glance, Yuno appears to be the perfect girlfriend: kind, sweet, and feminine. But beneath this facade lies a ruthless and calculating person who will do everything in his power to ensure her safety and, more importantly, Amano's.

She has no qualms about using violent means or taking advantage of others to achieve her goal—her and Amano's survival.

Yuno has yandere tendencies and will go to extremes if anyone tries to hurt Amano or take him away from her. She once considered using violence when she wondered if Amano's mother would object to their relationship. Fortunately, that didn't happen.

15. Hei (Darker than Black)

Hei is probably one of the darkest anime characters, despite not possessing a dark or evil nature. Everything about him, from his expressionless, blank face to his demeanor, exudes a dark vibe.

Known by the codename BK-201, Hei is an assassin who kills anyone on command. He silences targets who pose a threat to his organization, the Syndicate.

Hei, however, is a loner at heart. He never wanted to be a killer, but he had to take up arms to protect his sister, Bai.

After Bai disappears in the Heaven's Gate incident, Hei becomes colder and no longer hesitates to kill people, even if they are children.

What makes Hei special is that he never rationalizes his death. It's his job, so he does it. That's why he's such a lovable character, despite his dark side.

There you have it, the 15 best dark anime characters of all time. Did we miss anyone? Let us know in the comments.