The Killer Six Elements are a group of 6 different freshmen who along with their gangs gain control of the schools that they attended before deciding to apply for Ishiyama High School. The reasons for changing schools are different between each other. Whatever the reasons they change places is still unknown but the most famously are: to either standing as Ishiyama's top or for their personal greed. The only thing that is for certain is that they have their eyes on Oga who is Ishiyama boss.
The Killer Six Elements are divided in two categories according from what it seems to be base in power level or the strength that each one possess. The first category is The Three Kings who holds the ranking from 6° to 4° and The Three Beasts who who holds the ranking from 3° to 1°. According to the Solomon Company main member, it's being said that they all received demons from them and formed a contract later on. All of Elements' gangs have a power boost thanks to the contract their leaders holds and almost all of the gangs have the King Crest which can amplify their powers even further.
The Three Kings;
The top 6° to 4° member in strength along the new powers that came to recently rebuilt Ishiyama High School just below the Three Beasts. All of them possess a great amount of strength and combat capabilities. Making them alongside their a powerful threat to Ishiyama previous leaders. It's still not clearly enough between those three their actual rankings or powers yet.
Ebian Ichikawa: Also named Chrome Dome or the Blind Swordsman who wants to beat Oga and the "Saint Guys" to become Ishiyama top. He is a skilled swordsman and later revealed to have a contract with a demon making him a Spellmaster as well. Besides that information, nothing much is known about him yet.
Kankurō Akahoshi: Also named Fan That Dyes Everything Blood Red is a guy whose main objective is to stand at the top of Ishiyama making Oga the opponent he wants to beat. Despite being a Killer Six Element Akahoshi has never stated to be interested in monarchy and only wants to prove he's the best out there. He is very easy going and holds a striking resemblance with Oga himself besides his personality even stating that he won't gang up on him but beat him fair and square. Later it is revealed that he has a contract with a demon and apparently he is also a Spellmaster.
Ringo Hōjō: Also known as Tobacco for her liking to smoke and the only female member of the Killer Six Elements. Ringo was also the Second leader of the Red Tails and then she formed a new gang and attended Ishiyama. She has a manipulative personality and a obsession for winning. Her objectives seems to be Ishiyama top spot, so she is going after Oga and to settle the score she has with the Third leader Kunieda Aoi whose seems to hold some kind of grudge against each other. Ringo made an indirect temporary contract with Koma ( Aoi's pervert demon) without the first one knowing so the second one could get a better chance to be close to her attractive body and fondle her.
The Three Beasts:
The strongest three of the Ishiyama Killer Six Elements whose ranking apply according with the strength they possess apparently unlike the Three Kings. The three of them are Spellmaster and accordingly were the only ones of the six Elements to be able to master their demons.
Yōhei Nasu: The 3° rank member of the Three Beasts whose main targets are Oga Tatsumi and Beelzebub IV. An unpredictable guy who no one gets what he is thinking and alongside his bizarre personality makes him a dangerous threat to his opponents. Since the beginning he shows great interest not only in Oga himself but Baby Beel stating that when he beat Oga he will take the baby away from him. Later it is revealed that the reason he wants to beat Oga is so he can later take control of Baby Beel and form a contract with him gaining control over his immense demonic powers. It was later discover that he was also a Spellmaster whose demon belong to the Solomon Company.
Takamiya: The 2° rank member of the Three Beasts who apparently main target is Oga Tatsumi and gaining control over the school creating only one power that rules himself just like his nickname "Emperor" states. Takamiya Shinobu appears always to be a quiet guy with no interest in trivial matters who usually has a cold expression in his face all the time. Since his first appearance it can be seen a great interest in having a fight with no barriers against Oga which later on happens. He was taught how to control his demon's power by Zenjūrō Saotome discovering his natural talents to learns spells with a comprehension off the charts. He is Lucifer the demon lord who is consider "The Demon Lord of Demon Lords" Spellmaster.
Fuji:The 1° rank member of the Three Beasts and strongest member of the Killer Six Elements. Not so much is known to this day about Fuji since he hasn't show yet on Ishiyama, just that in his previous school gained that nickname of "Stongest Rookie Ever" and that he was a former pupil probably in his childhood of Zenjūrō Saotome which makes him also a Spellmaster. According to Saotome, Fuji was brimming with talent and is a very experienced Spellmaster just like Takamiya. It is imply that he has a bigger connection with the Solomon Company than any of the other Elements and by the words of the Company's executive that he is not only the strongest between the six of them but of Ishiyama itself surpassing even Oga Tatsumi that is currently Ishiyama strongest.
These characters are based upon the Seven Princes Of Hell