Akuyaku Reijou ni Nanka Narimasen. Watashi wa『Futsuu』no Koushaku Reijou desu! - Chapter 181: The West farm and Shushu-san.

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

Amid a world war, with his awakening to powerful special abilities (Soul Armor Abilities), Kamiya Yuusuke, conscripted into the military at the age of 10 due to this newfound power, continued to achieve numerous victories on the challenging battlefield. As a result, at the age of 15, he held the position of Brigadier General.Despite traversing battlefields worldwide, he finally managed to return to Japan. The joy of returning home was short-lived, as news of an underage boy in the military started to leak to the public. In response, the military high command ordered Yuusuke to attend a military school called the Special Operations Soul Armor Academy and undergo a revision of his military records.Yuusuke, secretly pleased at the prospect of reclaiming his youth, faced numerous troubles, whether due to the nature of the unique school or perhaps because he had been in constant battle since childhood. What will happen to his relationships with strong-willed girls such as his half-silver-haired childhood friend, the older sister officer who is his work partner, and the tsundere honor student of the same age?

Thrust into an enigmatic world born from bloodshed; venture inside its complexities, dark-side, and always changing nature. At the center, a boy; brought up by an exiled mage, steps into a life of independence. A test to try and change his life for the better after witnessing what war can do to a person. The walk towards finding a stable living gets toppled as a unique magical element awakens. Using people, toying with emotions, doing anything and everything to get what he wants, this is the life of the next Death Reaper. Mostly emotionless, life continues as questions about his state of mind and being remains clouded behind many personas.

This isn’t the story of a single man, it’s the story of a whole world. Read as the world builds itself from the ground up. Conspiracies, evil, the dark side of humanity. In addition, tis the start of a new age; the birth of monsters – a story depicting the tales of the first heroes and demons to ever exist.

The Wielder of Death Magic isn’t a typical fantasy. The heroes don’t summon forth power from heroes of old, here, the characters are the ones who make up the myths and legends for the next generation. Amidst the turmoil, Staxius, he lives on, watching and waiting as the world grows.

Cayena, the Imperial Princess, was known as the most beautiful woman in the Empire. She was a woman who knew nothing but evil and luxury.

However, she was destined for ruin: she would be used as a chess piece by her younger brother to secure his throne and killed by her crazy husband.

“I’ll make you the Emperor.”

“… Sister, are you referring to me?”

“In exchange, give me freedom.”

She had to change things before she became that Cayena.