From Today, I'm a Player - Chapter 220. A Single Serpent Pt. 7

At the height of her power, the Supreme Goddess Amane also known as the Beast princess sacrificed herself to save the life of children she had adopted throughout her life. That should have been the end of her story. Amane had achieved her ultimate goal of saving the lives of her loved ones and her sacrifice would give them all decent lives. But the Supreme Goddess felt her eyes opening in a new body and a new era. She had been reincarnated into the body of a Yoko Tsurugi, the mentally-challenged adopted daughter of the Tsuragi family (The family infamous for their beast-taming business) Reincarnated in a new body with no knowledge of why she had been brought back, Amane decided to embrace her new identity and live a carefree and easy-going life doing what she was known for before. She would do what the previous owner of her body was unable to do - Show everyone why you did not mess with her, the supreme tamer of beasts. The new era was different with no ‘alliance’ or distinction between races. The world was a calm place that seemed to have a place for everyone. Amane, now Yoko, should have a decent new life. But the past refuses to let Amane go and the circumstances behind her resurrection were becoming more and more complicated. It was more than clear that something seemed to be brewing in the background of this new era. And the balance of power was not as even as it first appeared to be. Who had called Amane back in her new body? And for what purpose was she brought back? These questions might be more important than they first appear to be.

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

In the end, war couldn’t be extinguished. But, there was a transformation. Even in the heart of a worthless accomplice in murder who was indifferently continuing his task, there was a transformation. The massive weapon “Object”.

This was a weapon that changed the whole definition of war. An exchange student named Quenser, who was dispatched to the battlefield, met at the base a girl with a strange aura. The girl, dubbed “Elite”, is the pilot of “Object”. The near future. This diminutive boy had come to take on the role of standing up against the strongest weapon “Object” for the sake of the girl. This was the motive for their first meeting.