Reborn with Steve Stand - Chapter 473 - 470: Cyttorak

Song Yan, a senior high school student, lost his parents when he was a child. Before obtaining a mysterious and amazing ring, he has been often plunged into a vulnerable position and easily marginalized. However, his life is changed because of the cryptic ring.

- Description from Novelupdates

He rose from hardship, but was felled by betrayal. From then on, one man, one gun; treads the path between Evernight and Daybreak to became a legend. No matter what was destined to be his fate, he intends to become the ruler who dictates.

I finally managed to kill the demon lord.