Shinmai Maou no Keiyakusha Wiki

Leohart Demon Lord.jpg
Name Leohart
Kanji レオハート
Rōmaji Reohāto
Age Unknown
Gender Male Male
Hair Color Purple
Eye Color Blue
White (While Fighting)
Personal Status
Status Alive
Relative(s) Unnamed Adoptive Parents
Liala (Adopted Older Sister)
Professional Status
Race Demon
Occupation Demon Lord
First Appearance
Light Novel Volume V
Voice Actor Kazuyuki Okitsu (Japanese)
Kyle McCarley (English)
Image Gallery

Leohart (レオハート Reohāto) is the current Demon Lord who lives in the Demon World, and he is also the younger adoptive brother of Liala.


Leohart is a tall young man with tanned skin, purple hair and blue eyes. When he fights his eyes become white and his sclera turns black. He is seen wearing bulky black armor with a purple cape. He also has large purple wings. In battle, he usually summons his large broadsword.


Leohart is a highly intelligent and powerful yet a relatively young demon. Although he maintains a calm and collected demeanor from a young age he has been driven by a hatred of the Demon Council and love for his adoptive sister and the demon world as a whole. Leohart despises the constant warring between the various demon factions and dreams of one day creating a united and peaceful world for he and his loved ones to live in, towards that end, he greatly desires to kill the members of the Demon Council which he perceives to be at the heart of the corruption in the demon world.

Unlike most of the demons, who are mostly cruel, selfish and power-hungry using their subordinates as a mere tool, Leohart deeply cares about them as he prevents them to interfere in his clash with Jin knowing they are no match for him. He also sends Lars to rescue Gardo after he was impressed. Leohart also trying to prevent unnecessary loss of life this is seen when he proposed a decisive battle with only a few elites from each Faction, to avoid them.


When Leohart was young, his parents were killed in one of the many demon civil wars and he ended up in an orphanage. He was adopted into a prestigious demon family who had in the past produced many demon lords. Shortly thereafter, he met his adoptive elder sister Liala whom due to having a beautiful appearance that was very similar to the Gods that the demons were descended from and who was their most hated enemy she was locked away and her existence covered up. Also, Leohart's new parents gave numerous Blood Transfusions to draw out his power and allow him to past any demon lord lineage tests.

Although Liala was the Daughter whose existence they had to hide for all their sake, and Leohart the son they had adopted as a replacement their parents loved them both very dearly, and he would fall in love with his sister. When Leohart first went to fight in the previous great demon war it was explained that it was planned by his parents for him to conceive a child with Liala and acquire a substitute wife who would pretend to be the child's mother and continue their line.

Unfortunately, his parents would die while he was away, and although he would not learn it until later, it was due to an assault by the Demon Council who learned of Liala's rare and beautiful appearance and sought to take her as a toy. After the death of the former Demon Lord Wilbert, he merged together with the Radical and Conservative Demon Factions by manipulating their hatred towards the gods into current Demon lord Faction and made their lord by the Demon Council who had hoped to be able to manipulate him by using his sister.

Instead, Leohart has quickly managed to amass a huge amount of influence and powerful direct subordinates such as the former Demon Lord Candidate Balflear or the young demon spy turned traitor from the Moderates Faction Lars who would become his closest confidants. After Wilbert's death, he attempted to protect his only daughter Mio Naruse with the intention of one day acquiring the demonic power that she inherited from her father as part of a plot to wipe out the Demon Council whom he regards as parasites and afterward peacefully unite the various warring demon factions and benevolently rules them. When her adoptive parents have killed his entrusted her protection to Lars.


Volume III

Leohart was seen walking with one of his men talking about Zolgear's disappearance and that it was unclear if he was dead, as it was reported a few just a moment ago. He ordered an investigation and to report to him at once. Thinking back to Lars' reports, he suspected that Zolgear was plotting something in secret, but was surprised a man of his power had been defeated. As he walked into the royal throne room, he saw eight men on the ground as Jin welcomed him back saying, "You're finally home, huh?" He got "tired of waiting" and was intrigued that the current Demon Lord was so young before explaining that he's there to 'Thank him back for looking after his kids'.

Volume IV

Leohart immediately recognized him, prompting Jin to remark that it's an honor that even the new Demon Lord recognizes his name and face. Jin would then go to say that he's here to pay him back for hurting his kids. The two Leohart and Jin would have a high-level battle, to which neither of them seemingly went all out. Although, Jin ended up retreating after seeing the immense power of Loki. Leohart had planned to use the battle to acquire even more influence by defeating the 'God of War Jin Toujo' but instead his influence had been weakened after Jin turned Loki's power back on him and escaped unscathed.

Volume VI

After Mio had been brought into Wildarts the capital city of the Moderate Demon Faction the Council forces Leohart to send the newly excavated 'Heroic Spirits' to attack Wildarts led by Balflear and the Council's plant Nebula, as well as secretly sending Lars to monitor the situation. After the disastrous attack was foiled by Basara Toujou and his servants Leohart had Lars rescue Balflear.

Volume VII

Following the attack, in order to avoid a full-scale war, Leohart instead proposes a seven on seven duels with the Moderates faction for Mio's power. Having sent his messenger Leohart then goes to visit his sister. Leohart attempts to defend the Hell Hound named Bearu who Liala was giving a bath when she ran off in abject terror from her by pointing out that she can't neuter her since she's not a he. The two bath together before going to bed and having sex together.

Before the two goes to sleep, Leohart reaffirms his desire to unite the two largest demon factions under one ruler, and create a world where his sister can live freely and happily.

Abilities and Powers

Demon Powers

Leonhart was honored as a War Hero in the previous war against the Hero Clan and fought on the frontlines. It is stated that since then, he has studied and reached even advanced levels of martial arts. Living up to the ranking of a Demon Lord, Leonhart wields incredible power able to hold his own against even Jin Toujou, who was hailed as the Strongest Hero and War God albeit, he wasn't serious. He was later able to overpower Basara in their fight a number of times, but he ultimately lost after he activated the powers he inherited from his mother. Leonhart was also strong enough to hold back Chaos for an extended period of time.

In Volume XI, it was revealed that he formed a Master-Servant Contract with his adoptive sister, Liala bringing out his hidden power and wield Loki's full power making him stronger than before, letting him both defeat Balflear and Legion. Afterward, it was later revealed that Leohart could potentially rival Basara and Shiba.

  • Immense Strength: Leohart possesses great physical strength, easily hold against Jin on his own and can endure Basara gravity slash for some time before falling. In Volume 7, he has proven to be able to outclass Basara throughout their fight with Jin stating that his son's chances of winning were 20 percent and he has proven strong enough to wound Chaos.
  • Immense Speed: Despite not as fast as Basara, he has speed and reflex are enough to react to his attacks and keep up with him to a certain degree. Leohart was fast enough to avoid many assaults from Chaos.
  • Master-Servant Contract (Servant): After his defeat in Volume VII, Leohart realized that Basara's strength almost all his own and it was also rooted in the bonds that he shared with those closest to him. And for that reason, he chose to tie a Master-Servant Contract with Liala to become her Knight, causing him to become stronger than ever due to the powerful bond and trust between them.

Master Swordsman: Leohart has shown immense skill as a swordsman being able to hold his own against Jin in their initial encounter and fight against Basara despite their speed difference, then he overwhelmed him using his superior strength and slashing his sword to cause shockwaves.

  • Dimension Slash Counter: A counter that he used to cancel out the Dimension Slash Basara used against him, through Leohart performing a similar method of putting Loki into its dimensional storage before bringing it back causing his own dimensional distortion interrupting Basara's Dimensional Slash thus turning it into a normal slash.

Other Skills

Keen Intellect: Like Basara, he has a remarkable intellect as stated by Balflear who noted that he never needed to be his attendant, which was proven as he could gain some insight about his past and secrets after hearing the details about Shiba. As the Demon Lord, he can also realize the ramifications of his decisions and also realizing what his older sister would do if he died, turning her anger toward everyone responsible.


At its full power, Loki surpasses Wraith in terms of dimension manipulation. This is what allowed him to pinpoint Balflear's location amidst a space with almost limitless phase contrast.

— According to Uesu's narration

Demon Lord Sword, Loki

Loki (ロキ, Roki): This is a black demon sword hailed as being one of the strongest, which Jin called the "Sword of the Demon Lord", but it's still a far cry from rivaling Brynhildr. Loki has magic circuits built into it, letting him channel his powers into it to release its limiters, unleashing a black torrent classified as an "Annihilation Attack" able to devour the body and soul of its victims while tearing apart dimensions. Although, he couldn't bring out its full power as a forced attempt would result in his body and heart being overwhelmed. This all changed after Leohart formed a Master-Servant Contract with Liala and donned a jet-black full-bodied armor, letting him cut through dimensions and enter the Wraith's dimension.


  • The name Leohart could be a variant of the German and Dutch name Leonhardt composed of the elements leo 'lion' + hard, 'hardy', 'brave', 'strong'.
  • In Volume VIII, it was revealed that his adoptive parents transfused a lot of their blood to Leohart to ensure that no suspicions would arise about his adoption.