Maxwell

Background
Having stalked Ignis Fatuus in the past before he got defeated by You's father, he now joins the Ouroboros Alliance and starts to stalk Willo-O-Wisp's leader again. To the point of attacking the Community.

Appearance
Light brown hair that has a center parting. And pure white clothing that seems like snow.

Personality
A stalker who has a somewhat narcissistic character who believes that people are running away from him because they are too in love with him but too shy to admit it. In short, he's a perverted threat to Ignis Fatuus. However, this is also a very good point about him that everyone likes to make use of.

Relationships
Willa-the-Ignis-Fatuus - His love-love target that makes him go crazy.

Yō Kasukabe - Maxwell feared her power as he identified it as the Gift similar to his first defeat in his life. However, that fear was replaced with confidence after acquiring knowledge from the combat analysis.

Koumei Kasukabe - Defeated him once and saved Willa in the past. Made a second appearance that led Maxwell to unleash his angels in fear.

Plot
Sent by the Ouroboros Alliance as a pretext to help the sub group of [ His Highness]. He's suspicious of their actions and seeks to monitor them as much as he can. As much as he can. In other words, he only does that when he lost his target of fancy: Ignis Fatuus.

To counter his spying, Rin always distracts him by giving him the task of looking for Ignis Fatuus which she glorifies the act as a knight saving a princess.

Gift and Abilities
[Phase Gate] - A summoning Gift.
 * Teleportation: As a demon who controlled the boundaries, Maxwell possessed the strongest technique of opening an [Astral Gate] to jump from outer worlds with a different time flow to the same time-stream—aka [teleportation] like Willia. His teleportation jumps between two points in the same material plane and he can easily teleport anyone far away as he teleported both Black Rabbit and Asuka from Kouen city to a forest with only a snap of his finger. Even Izayoi couldn't keep up with Maxwell's teleportation when he fought him in volume 11. He also used his Gift [Phase Gate] to summon the clones of Azi Dahaka.
 * Control the boundaries of heat: Being a demon which have the ability to manipulate the boundaries of heat, Maxwell has various abilities of thermokinesis. Both of his hands can shoot out whether a barrage of ice shards, freezing blizzard or flames and fire storms. In volume 7, Maxwell summoned an army of Celtic Titan by opened the portal between [warmth] and [cold] after he released a fiery storm from his right hand and churning up a blizzard on his left. In volume 10, both Aura's lightning and Graiya's flames shot towards himself were easlity got deflected by an explosion caused by the control of heat to create a sharp temperature difference in the atmosphere. It was stated that if Maxwell used the full potential of this ability, he would have the potential to vaporise a small country in an instant.
 * Necrosis: By directly injecting cold air into the victim's mouth to steal heat and decreased body temperature, he could cause cell decay and lead to death. Not even Izayoi could survive this although he had a strong body.
 * Enhanced Durability: Maxwell capable of withstanding a shower of fiery bullets shot by the Lesser Dragons and the Salamander army without any scratches. However Maxwell is not really durable, he easily got burned by Willa's Azure Flames and Yō's attack could harmed him. In volume 10, both Almathea and Asuka obliterated his whole body by their combined attacks. Izayoi also pulverized Maxwell's face with only a punch in volume 11. It has been stated in volume 7 that he was one of the few Demons that could be defeated through the use of physical attacks.
 * Regeneration: Although Maxwell's durability is not durable, he still got regenerative ability. In volume 7, he got incinerated into pieces by Willa's Azure Flames which could burn anything that existed in the world as a material form or even the target was the Demon materialization of a concept but then his burned head and other parts of his body reattached themselves. In volume 8, Maxwell's body got vaporized by the flames of pseudo-divinity that destroyed Azi Dahaka's clones from the combined attacks of Asuka and Almathea but his body repaired itself in an instant and in volume 11, his face got pulverized by Izayoi's punch but he also regenerated it instantly.
 * Flight: Maxwell can levitate himself and fly.
 * Coppelia sisters--- summoning a legion of combat dolls that dance with flashing blades at their joints.
 * Nano-angel: Call powerful war machine that has the appearance of an angel equipped armor, sword and spear. A strike from an angel is strong enough to stop His Highness in his steps and if it were any of the others such as Graiya or Aura, they would be cleanly punctured to their deaths with that attack. His Highness stated that though they are only capable of simple movements, their strength and ability to jump between dimensions is a shocking threat. Rin also stạted that the angels can multiply infinitely and the threat from Maxwell could even compare with Azi Dahaka.

Trivia

 * Unlike the other demon lord, which came from mythology, Maxwell came from the theory of thermodynamics that was written by James Clerk Maxwell in 1867 (Maxwell Demon).
 * Its been stated that Maxwell caused a Paradigm Shift in the year 2020.