Naruto: The Hidden Protector - Chapter 82: A decision that affects the whole clan.

The main character is reborn as a character from a game he played in his previous life. This character falls into ruin along with the villainess, spending the last of their years together. A man named Kururi Helan.

In a world where strength determines one’s future, William, an orphan with no extraordinary talents, faces a grim destiny—until a brutal attack leaves him clinging to life. Instead of death, he awakens to a mysterious and powerful entity lurking within his mind: the Shadow System, a game-like interface that promises him unimaginable power. But this power comes with dark secrets, and refusing it would mean his death. Forced into a pact with a voice that can hear his every thought, William must navigate a dangerous new reality where shadow abilities and celestial power collide. As he enters the prestigious military academy, his newfound abilities draw both allies and enemies, all while a deadly conspiracy brews in the shadows. With the odds stacked against him, William must unravel the mystery of the Shadow System and decide whether to embrace the darkness within—or be consumed by it. His journey from a bullied outcast to a potential god will challenge not just his survival, but his very humanity. Power always comes at a cost—will William be able to pay the price? “What am I?” William asked the system. The system’s voice echoed in his head, cold and indifferent. “You are nothing.”

He has been abandoned by his clan.

He has been considered waste from his childhood but he is a “Peerless Genius”.

His father with the help of another person has sealed his Dantian to stop him exposing his exceptional talent but after his rebirth, he becomes the most dazzling star of the continent. However he faces crisis and difficulties as his Dao goes against the Heaven’s will.

Overcoming everything, eventually he achieves the highest boundary “The God of War”.

- Description from Novelupdates

There are a total of seven sins, and a revelation is made to a young man named Alex that he is destined to become a demon lord, more especially a demon lord of sin called LUST.

It's not like he can change that and because he always knew something about himself was different—not in a physical sense, well, maybe a little—and not in a mental sense—but rather because he is thrown into a demonic war that compels him to accept his new reality.

He was only aware of a difference in himself. Relating to him and the ladies who are drawn to him... Well, it was more or less like he was a magnet in front of all the girls, and all the girls were drawn to him like a metal.