Diehauser told everyone how he got involved with the Khaos Brigade. But since Kisuke was listening, he started from the very start.
The Belial Clan is a very tight-knit family. Even if they came from a branch family, each one of them treated everyone with respect and love, which was very rare for a noble Devil Clan.
Cleria's mother died in the Civil War between the Old and New Satan Factions when she was still small, so her father and cousin took great care of her in her mother's place.
A while later, Cleria's father remarried and got together with a Human girl which became Sarah, or Sakura's, mother. However, due to the complexity of Sakura's birth, her mother couldn't take it and passed on soon after. Cleria and Sakura's father grieved at the loss of another loved one, but he still persevered for his daughters.
At this point in time, Diehauser vowed to get stronger for his family and trained himself with the utmost effort. But at that time, the Belial territory's economy was still not in a good condition due to the long-term after-effects of the Civil War, and the clan prioritized their citizens for them to live in ease and peace.
For Diehauser to join the Rating Games, a considerable amount of money was needed as it's a system for High-Class Devils and above. Although they were also high-ranking nobles, their wealth couldn't be compared to others.
However, even though Diehauser's mother was very against him joining the Rating Games due to its dangers, she also supported him when she couldn't convince him, by selling all of her valuable jewelry to fund his education.
His father, the Lord of Belial Clan, on the other hand, sold the unoccupied and unused land and some non-essential businesses they had to other nobles, to add more to that fund.
But thanks to their sacrifices, Diehauser was able to study in a prestigious school and was able to meet almost all of his servants right now that helped him to become strong and successful. A few more years had passed and Diehauser soon became the first ranker of the Rating Games, dubbing him and his peerage as the strongest within the Underworld except for the Devil Kings.
Soon after, he also inherited the position of his father and was able to bring the Clan to glory and riches. However, even with wealth, the small clan didn't lose themselves and continued their way as the benevolent Lords of the Belial territory.
Of course, life doesn't always go up. Thanks to Diehauser's success and rise in power, other Clans, especially those who they didn't get along with, couldn't help but be jealous and fear them.
But instead of Diehauser who they couldn't easily touch, they targeted another rising star of the Belial Clan, Sarah Belial. A genius who contributed greatly to the research regarding the reincarnated and half Devils. Despite some questionable points of her research, she helped the development of the Evil Piece System by making it easier for those becoming Devils, to adapt to their new bodies.
Sarah, while with her father and rare Human servant in her personal laboratory, was attacked. Due to the suddenness of the situation, all the guards in place were instantly massacred. Knowing that they were in a very bad situation, Sarah's father used his own life to block the enemies' advance and asked the Human servant, Ryouta Urahara, to escape with Sarah.
When Diehauser arrived, it was already too late as he only found the dying father, telling him what happened. In a rage, Diehauser chased after the Devils that attacked the laboratory but most of them already escaped and those who were captured refused to talk and killed themselves.
The Belial Clan also tried to search for Sarah and Ryouta's whereabouts, but as they did, evidence of Sakura's supposed malpractice came to light, and the higher-ups of Devil Society issued a warrant for her arrest.
The Belial Clan was, of course, shocked by this, but even more so, they were enraged. They hadn't been able to properly mourn for the fallen Belial member, and here they are being attacked yet again, from a different angle.
And after that, Sarah and Ryouta never appeared in front of them again, not even a bit of news from them.
What's worse is that they were not able to find the main perpetrator of the attack and weren't even sure if it was just a single clan, or a collective effort. Not just that, the attack on them became a different story altogether and it was told to the public that Sarah escaped with her Human servant.
After a few years of grief at the loss of both her father and sister, Cleria decided to come to the Human world to search for her missing sister. Soon after, she became the Lord of Kuoh Town and used it as her base for the search.
But after a decade, there was still no news regarding Sarah and Ryouta. It was then that another misfortune befell the Belial Clan as the Exorcists from the church assassinated Cleria due to her being in a relationship with an Exorcist.
Diehauser couldn't take the news and tried to invade the Human World to attack those from the church, however, he was stopped by Zekram Bael, a Devil that has more authority than the four Devil Kings.
After asking for a reason, Zekram told him that they didn't want another war with Heaven and he would stop him even if it means using force to do so.
Diehauser and the rest of the Belial Clan had to swallow their anger due to this. They knew that they'd just be destroyed if they were to go against them and Diehauser, as the head of the Clan, didn't want that.
However, he noticed the strangeness in Zekram's actions and investigated it secretly. This time, he figured out what really happened. It seemed that in her investigation she found out many things, Cleria was able to discover the existence of the forbidden King Piece and he used the fact that she went into a relationship with their enemy to silence her.
At that point, Diehauser's grief and rage reached the peak, he vowed to take revenge against Zekram. It was also that time that he got invited to the organization that aimed to destroy the current system.
For the last decade, Diehauser had been acting as a spy for a faction called 'Qlippoth', which is led by the prince of the almost extinct Lucifer Clan, Rizevim Livan Lucifer.
"Of course, I never intended to destroy the Underworld or the other worlds. I just wanted to get back at Zekram Bael and only shared information that would be detrimental to him and his clan."
With that, Diehauser finished his story. He then looked towards Cleria and Sakura, "But even If I didn't intend to do that, if you didn't appear in front of me again, I might have devolved into something that cannot be forgiven, no matter what."
After that, Diehauser faced Kisuke and bowed down his head, "For that, I would like to express my utmost gratitude for leading them to me."
"Although it was only started as a coincidence, I'm really glad that I was able to help," replied Kisuke. Deep inside, he wasn't just thankful that he was able to coincidentally save a relative, but he's also very thankful that he was born into such a family.
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Editors:
28th00: So, backstory chapter, huh? But yeah, this clan gets majorly screwed over in canon. It's not cool yo. Didn't Cleria ascend to heaven too? As a devil, she ascended to literal heaven, right? It's been a long time since I read volume 18, but that's how I hear it went down.
Goyya: To be honest, I don't really remember that part.
Staz Irvine