Super Detective in the Fictional World - Chapter 14: Footprints, and Staying Behind

The story is about a boy entering high school, who answers a strange call from a public phone one night. The caller challenges him to a bet: She’ll remove the birthmark which he sees as the cause of so many problems, and he’ll have fifty days to win the heart of a girl he’d considered far beyond his reach. And with this, a very strange summer begins.

Lin Wudao has traversed, and there is an invincible corpse collection system.

As long as you collect the corpses for the strong, you can get the things they owned or touched as rewards during their lifetime, and the obtained items are still strengthened.

Lowest, ten times stronger!

[You collected the corpse of the great emperor Jiang Taichu, and gained ten thousand years of cultivation! 】

[You collected the body of your fiancée Jiang Qingxue, obtained the Zichen Sword, a humane spirit weapon, and after strengthening it ten times, it was upgraded to become an extreme spirit weapon, the Xuantian Ancient Sword! 】

[You collected the bones of an immortal, obtained a ray of immortal origin, enhanced it by 100,000 times, and upgraded it to become the original origin of Hongmeng. After refining it, you can be promoted to the immortal emperor! 】

…

Since obtaining the invincible corpse collection system, Lin Wudao has embarked on an invincible road that can push through the ages and suppress the heavens.

- Description from novelbuddy

He is an undead who is devoid of all humanity, he is the one and only supreme overlord, he is a man who has severe mysophobia.