The Four Great Leaders of Tokyo

The Four Great Leaders of Tokyo is a term used to describe the Leader of the Four districts in Japan. The Four districts having the titles Heaven, Hell, Valhalla, and Watcher. Each Leader was chosen and groomed by the former Leader and while some were friends or are considered on friendly term they maintain the "status quo" set down by their predecessors. While it's rarely they come together or cross paths on friendly terms, in times of Great danger to tokyo or the world as a whole they are known to unify.

Each of the Great Leaders have a second-in-command who is typically a young or powerful child they took a great interest in. In terms of raw power, Ex Gremory is confirmed to have the highest amount.

Summary
Each member of the Four Great Leaders is typically a supernatural creature who acts as the leader over the other supernatural leaders living in their district, when they decide to settle down or leave Japan they will turn their title over to their predecessors. Cao Cao inherited his status at the age of 15 while the other three inherited theirs once they were much older. Aurora stated after the fight for the demon sword that the four Leaders weren't fighting at full strength because if they did so, this would start a riot by the other supernatural creatures that would completely destroy Tokyo.

Ex Gremory IV
"Always trust in your power"

- Ex Gremory

The Leader of the South District of Tokyo known as "Hell", a noble and powerful devil that possesses a aura of authority that shakes even creatures who don't know that he is the descendant of the hero Issei Hyoudou and Rias Gremory. He chose to take over the position due to his lack of regard over his clan name and not wanting to be known as the "Gremory" descendant of Legendary Heroes. He possess the Boosted Gear Replica and is a master in the Power of Destruction. In terms of raw power he is the strongest.

Ariel Quarta
"Maintain Peace and Protect the Innocent"

- Ariel Quarta's Oath

The Leader of North District of Tokyo known as "Heaven", considered "anti-Ex" she is shown to be strict, kind, and caring to a almost insufferable degree. Due to this care for maintaining peace in Tokyo, she is shown to constantly try to break up Semyaza and Ex's fights, the two using this to their advantage to steal the demon sword. She is affiliated with the Tokyo Police Force and Churches to try to prevent Ex's illegal activities.

Semyaza
"Live for something"

- Semyaza Jr.

The Leader of the East district of Tokyo known as "Watcher", a former young angel who was a childhood friend of Ariel Quarta, he decided to fall, not wanting to be held back by Heaven and it's ideals. Being a young and weak angel he eventually worked his way up and supported Azazel Jr.'s dream of bringing fallen angels to glory. He is shown to be the one who fights the most, constantly getting into battles with Ex Gremory's. He's also known for supporting gangs that rival the ones Ex Gremory's supports. Ex Gremory constantly refers to him as a "bug that won't go away". Yami later states that Semyaza is nothing more than a competitive child who doesn't like the idea of someone besting him but loves to test his strength. Semyaza later admits that he suffers from eight-grader syndrome and relies on Azazel Jr. to fund his living due to not having a job or any income of his own.

Cao Cao
"I will never be forgotten, you'll remember my strength!"

- Cao Cao's Promise

The Leader of the West district of Tokyo known as "Valhalla" descendant of Cao Cao and wielder of the Excalibur Destruction. He is shown to be a arrogant and hostile young man who dislikes the three main factions due to them dominating the supernatural world while humans and Demi-Gods are constantly being ignored and neglected due to the intense focus that Issei Hyoudou brought to the Underworld. Cao Cao is shown to be highly competitive and wants to prove to the Heavens and Gods that his district is worth focusing on. Despite this attitude he does have a code of honor as he refused to take Yami down, due to how weaker he was compared to him and instead commanded his second-in-command to fight on his behalf. In terms of strategy he is said to be the greatest. Despite becoming a leader at 15, much younger than the other Leaders, he is the youngest of them all being only 18. He expresses no fear of dying, even saying he would give his life up if it would allow him to prove his strength.

He possesses the ability to control spirits to a extent however he rarely uses this, instead relying on touki and his own skill and strength. Some say his use with the Excalibur destruction is almost equal to a young Xenovia.

Second-In-Commands
The Second-In-Command commonly known as Knights of the Four is the term used to describe the Four young supernatural creatures who act as the "co-leaders" for the Four Great Leaders. It is stated that each is a young creature with immense power and strength that when fully mastered could destroy the World. Ex Gremory arrogantly states that under the Four Great Leader's guidance they will become high political figures and even weapons of the larger supernatural world in the future.

Trusted Officials
The Trusted Officials is the term used to describe who each of the leaders trust the most and would even trust with their life. While not a official ranking, Eden states that everyone who was there during the demon sword incident is among this rank because they wouldn't be there unless the Leaders trusted them due to not wanting to risk the start a riot or full-out war that would destroy Tokyo. Ex Gremory later states that Rebecca and Celina are among his circle however because they were young high-class devils, he didn't want them to fight for Aurora and her servants, with Yami being the primary reason for Ex Gremory's involvement.

Ex's Circle

 * Yami Himura
 * Aurora Lucifer
 * Shiro Yuki-Queen
 * Taira-Knight
 * Rebecca Phenex
 * Judai Aki
 * Celina Abbadon

Ariel's Circle

 * Hope
 * Ryuk Dragneel
 * Tristan-Ace of Heart
 * Olivia La' Barre- Queen of Hearts
 * Yuri Weiseman
 * Yako Weiseman

Trivia

 * Despite Ex Gremory's constant appearance in Class 4-C Ariel has the most children in that classroom among her inner circle with Hope acting as her second-in-command.
 * Due to the lack of a threat, Ex Gremory and Ariel only have a few of their servants living with them in Tokyo, with most of them spread throughout the world working on their own objectives and goals. Ex Gremory states that he doesn't have much concern what his servants do, due to his laid back personality, while Ariel has her servants working alongside different churches of their choosing around the world.