Mammon

, also referred to as, is a Demon who is a former ruler of one of the Demon World's countries prior to its unification, thereby being a member of the Seven Deadly Sins. He is currently residing in the Human World with Kankurō Akahoshi.

Appearance
Mammon appears to be a short, skinny young man with plain, dark eyes. He has a distinctive mouth that vaguely resembles a suction-cup and has a perpetual blush. These features serve to give him something of a cartoonish face.

Mammon is primarily exposed aside from wearing a light-colored sheet around his waist, similarly to a kind of skirt, with a flap hanging down from the back. The sheet is rather small as it does not even cover Mammon's knees. He wears bandages over his chest that cover the upper half of his body underneath his pectoral muscles. Mammon also wears a sheet over his head that covers his whole scalp. There are bows to keep the sheet intact on the left side of his jaw and over his right eyebrow; the top bow is also connected to a light-colored band that goes underneath the sheet.

Mammon's unique but comical appearance has shocked several characters, including the Demons Lamia and Alaindelon, with the former remarking to herself from her first look at Mammon that he cannot truly be a member of the Seven Deadly Sins. Notably, Akinori of the Solomon Company has also expressed surprise at seeing Mammon's appearance and, having seen the Demon before, wonders whether he has always looked like that.

Mammon typically takes on the form of a fire spirit when utilizing his powers. In this form, his entire body is composed entirely of wispy flames; even his face appears to simply be slanted dark spots for eyes and a mouth. Several components of this flame body may change form, taking up more solid appearances such as a right fist.

Personality
Mammon is a rather greedy person and appears to only offer his assistance to others if promised monetary payment, as shown with his interactions with Kankurō Akahoshi when the latter requires his services; Mammon even acknowledges this flaw and has admitted that he is not a good Samaritan because of that. However, it appears that Mammon does not always require monetary payment whenever he is needed by his Spell Master.

According to Akahoshi, this greediness appears to stem from the fact that Mammon is "totally underhanded" when it comes to money.

Mammon also appears to be somewhat indecisive which attributes to his somewhat light-hearted and friendly nature; while he was being called to help Takayuki Furuichi, he originally stated that he was unsure if he could really help the teenager, later stating repeatedly that something bad might occur to Furuichi if his "soul" is not reunited and brought back to his body by the end of the day, much to Lamia's disappointment.

Additionally, Mammon tends to laugh a lot in a "hyup" mannerism.

History
Before Beelzebub III united the Demon World under his rule, Mammon was the ruler of one of its countries.

Mammon eventually fell into the hands of the Solomon Company sometime after, subsequently becoming contracted with the high school student, Kankurō Akahoshi.

Return to Ishiyama High School Arc
While Akahoshi is in Takayuki Furuichi's room to offer his assistance, he calls for Mammon. Mammon quickly appears and begins discussing with Akahoshi on whether he is able to heal the teenager, which he admits that he is unsure of; nevertheless, he reminds Akahoshi that he will need a "pretty penny" should he do anything. Later, Mammon rubs his head with embarrassment when Akahoshi remarks over his medical skills and even explains afterwards on what he can do to save Furuichi. Mammon suddenly remarks that Furuichi is in grave condition and that he believes something bad will happen to him if his "soul" is not reunited by the end of the day.

Mammon returns to fight alongside Akahoshi when the latter calls for him. Mammon, manifesting himself as a fiery spirit, forms around Akahoshi before then proceeding to use Red Bullet, incinerating a massive part of the Zodiac Demon Libra's chest. Afterwards, Mammon returns to his original appearance as he complains over the heat of the lingering flames.

Powers & Abilities
Pyrokinesis: Mammon's main power is the ability to conjure and manipulate fire. He is very proficient in using powerful flames, which alone is strong enough to blaze through the ground and mutilate a Zodiac Demon's body with ease. Moreover, it has been stated that Mammon can also use his fire for medical purposes, which appears to be a skill that only he can use.
 * Mammon uses his right fist to deliver a powerful punch to his opponent. Upon impact, his punch becomes a massive and fiery first that can easily incinerate through the body of a Zodiac Demon, leaving an empty hole inside of them.

Medical Doctor: Mammon appears skilled as a medical doctor. When called to aid Takayuki Furuichi, whose "soul" has been extracted and mutilated outside his body, he claims that he will be able to bind his "soul" together for the time being and that he can even extend his life slowly for a certain price; these skills appear to be unknown by Lamia, medical apprentice to the doctor Furcas Rachmaninoff.

Kankurō Akahoshi
Mammon and Akahoshi have a friendly yet still professional relationship.

Mammon is usually away from Akahoshi when unneeded, though when his services are required, he is very punctual with his arrivals. However, Mammon always requires monetary payment from Akahoshi for his requests; evidently, Akahoshi has required the Demon's assistance on several occasions as Mammon apparently has a tab on the high school student. Nonetheless, Mammon is loyal and obedient to his Spell Master's commands so long as the arranged payments are to be taken care of; however, this appears to extend only towards non-combative needs as Mammon does not ask for money beforehand whenever Akahoshi wants to utilize pyrokinesis.

Trivia

 * In Christian mythology, Mammon is one of the seven princes of Hell, representing the sin of greed.