Over the centuries, countless characters have made unfortunate deals with the devil. Symbolically or literally, those who do often get more than they bargain for, and relationships with monsters lead to misfortune for everyone involved.

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In the realm of anime, demonic characters feature prominently in the fantasy and paranormal subgenre. Many shows make use of demonic or otherworldly powers, and frequently enough, heroic characters must work with monsters to get things done. While some demons aren't worth the trouble, others become amazing allies and characters in their own right.

10 Jujutsu Kaisen's Characters Have Some Demonic Allies

megumi using his cursed energy against sukuna in jujutsu kaisen

Jujutsu Kaisen won over a lot of shonen fans in the late months of 2020, and for good reason. A stellar cast of characters, a dark and often violent premise, and monsters galore all came to life thanks to MAPPA's excellent animation. Where Jujutsu Kaisen falls a bit short, arguably, is in its terminology. It can be confusing to distinguish between jujutsu-shi (sorcerers), jusu-shi (curse users), jujutsu (the sorcery itself), juryoku (cursed energy), and noroi (curses themselves).

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But in a colloquial context, the cursed spirit Sukuna and the rest can be equivocated to "demons" in a Western sense. While it can be argued that Yuji has to repress and use Sukuna's power rather than work with him, other jujutsu sorcerers also use cursed spirits to get things done. For instance, Megumi summons shikigami, akin to demons or small gods, to aid him in his battles.

9 Maou-Sama Is A Devil But His Co-Workers Are Human (The Devil Is A Part-Timer)

satan, alciel and Emilia (The Devil Is A Part Timer):

While most demons appear in action or horror-fantasy series, every so often they take center stage in a comedy. Such is the case in The Devil Is Part-Timer, which brings the idiom of "giving the devil his due" to a very literal conclusion.

Stranded in modern-day Japan without his powers, the Demon King Satan must make a living just like everyone else, so he gets a job. Working at MgRonald's, Maou-Sama becomes a devoted employee and solid friend to his human coworkers, a tenacious ally in the fight for fast-food supremacy.

8 Even The Son Of Satan Needs Friends (Blue Exorcist)

Rin and Yukio from Blue Exorcist.

Family drama factors into everyone's life, but it's hard to fathom how Yukio manages to cope with his circumstances. Raised by a priest, Yukio and his unruly twin brother, Rin, believe in good and evil, heaven and hell.

Things get complicated when audiences learn that Yukio is secretly an exorcist and Rin is the son of Satan, a half-demon capable of destroying the world. Brotherly squabbles aside, Rin deserves the benefit of the doubt, and his charisma wins him lots of friends. Just because he's a demon doesn't mean he's a bad guy, after all.

7 Ciel And Sebastian Have An Arrangement (Black Butler)

Ciel and Sebastian from Black Butler

If any character is following the textbook Faustian model for dealing with devils, it's Ciel Phantomhive of Black Butler. After his parents are mysteriously, brutally murdered, Ciel survives and goes on to make a deal with a demon. Sebastian Michaelis serves Ciel under the guise of being his butler but holds the contract to Ciel's immortal soul.

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The relationship between Ciel and Sebastian is complex and undoubtedly sinister, despite what fandom might pretend. But the dynamic is always interesting, even when it's clearly toxic.

6 Siblings Can Overcome Even Demonic Differences (Demon Slayer)

kamado and nezuko tanjiro from demon slayer

Siblings make for great protagonists. Most audiences can relate to the bond that exists between brothers and sisters, and some of the best series of all time feature this relationship front and center. Recently, Tanjiro and Nezuko of Demon Slayer have charmed fans around the world.

Even after his little sister Nezuko is transformed into a demon, Tanjiro refuses to give up on her. Nezuko is Tanjiro's sole surviving family member, and, demon or not, he sees that she's still at least partially the girl she always was. He'll protect her at any cost, and she'll do the same for him.

5 Devilman Is The Product Of Ryo's Misdeeds (Devilman Crybaby)

Devilman Crybaby

It's not really fair to say that Akira and Ryo work together in Devilman Crybaby. It's Ryo's fault that Akira becomes fused with a demon in the first place, and his reasons for manipulating his so-called best friend are nefarious indeed.

But rather than being overcome by the demon Amon, Akira's good nature and strong will allow him to overpower and control the monster within him. Akira works within his circumstances to become a dark crusader, Devilman, and mostly uses his newfound abilities for good.

4 Raizen Was A Demon King (Yu Yu Hakusho)

raizen of yu yu hakusho

Yu Yu Hakusho is among the most beloved shonen series to indulge in the supernatural, and many of its characters fit into the demonic category. Notable among these is Raizen, a former Demon King who swore never to eat humans again after falling in love with a human woman.

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Series protagonist Yusuke is actually a descendant of Raizen, though he doesn't know it, and Raizen possesses him during a battle against Shinobu Sensui.

3 Staz Is A Huge Otaku, And Also A Vampire In The Demon World (Blood Lad)

blood lad is about a group of supernatural friends in search for life-restoring magic.

Blood Lad is another series that casts demons in a more humorous, upbeat light. The protagonist, Staz Charlie Blood, is a vampire with a love for otaku goods. He lives in the demon world, but cares more about anime than he does about drinking blood.

Over the course of the series, Staz befriends a human girl named Fuyumi Yanagi. All Staz wants is to travel to Fuyumi's world, where anime merch exists aplenty, and soon enough the story becomes an oddball meet-cute of demonic and familiar worlds.

2 Kagome Gets To Know A Lot Of Demons (Inuyasha)

Inuyasha

When Kagome falls down a well and finds herself in a magical version of the Sengoku period, meeting demons becomes commonplace. Inuyasha himself is half-demon, half-human, although the show's demons are a bit more diverse than demons are in the traditional Western sense.

Borrowing from yokai folklore especially, characters range from dog demons to tree demons and horse demons and beyond. While different demons have different strengths, most of them long to become more powerful, and Inuyasha is no exception to this rule.

1 Claymore's Cast Is Composed Of Human-Demon Hybrids

Clare From Claymore

Claymore's approach to the demonic is much darker than what's seen in most shonen series. In this medieval fantasy world, demons called youma torment humans and devour them.

Yet the protagonist of the series and all other claymores, or warriors, are half-human and half-youma. The product of cruel experimentation on children, the claymores exist to slay true youma. Though imbued with inhuman strength and agility, the claymores can be corrupted by their youma nature, meaning they too must be killed. As dark fantasy series go, Claymore doesn't pull punches.

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