Kantan na Monitor desu - Reaper Game 03: Reversal

[Unique Characteristic: You acquire ‘Protective Instinct’ (保護本能).]

The world’s top level hacker, Shi Lei; due to him hacking the world’s top military powers during a joint exercise and attempting to steal information from them, ultimately leads him to get sold out by his own organization. This act eventually caused his own death by a missile bombardment.

God was playing a joke on him and allowed him to return back to six years ago, the autumn season of when he was still at his university. Being given another chance, plus the fact that he retained his ability as one of the best in hacking technology, Shi Lei decided to change his life! During his previous life, he was only an assassin in the dark. Although such an existence made people afraid of him, he would have to always hide within the shadows. In his new life, not only does he want to be an assassin in the dark, he also wants to stand openly in the middle of the world stage. Creating a world-class super enterprise, he will single handy change the whole world!

- Description from Novelupdates

The main character has been reincarnated, and he possesses a system and a powerful treasure. Using these, he plans to create his own universe. Keep reading to find out more.

In a world fractured by conflict and haunted by shadows of the past, Kokushibo—the first Upper Moon demon—meets his end, only to awaken in a new life. Reincarnated as Crimson, a child born into a different family, he carries the memories of a past he cannot escape. Burdened by centuries of guilt yet indifferent to the present, he resigns himself to duty—until an unexpected bond with his newfound family begins to thaw his hardened heart. As he struggles between the weight of his past and the weight of the new life, Crimson must decide whether he will remain shackled to his former sins or embrace the possibility of peace.