Others Cultivate for a Century, but You Become a God in One Second by Slaying Demons?

On the very first day after transmigrating, someone ran a blade straight through his chest.

Behind him was the brother who had sold him out. Before him was an ape demon eager to eat his flesh. In his arms lay a girl who had been sent to become a demon's concubine.

His predecessor was a crooked constable who delivered people to demons. He deserved to die.

But Lin Yuan didn't.

In his previous life, he had died suddenly in a rented apartment, and no one even claimed his body. Now that he'd finally gotten another chance at life, why should he become a tonic for beasts?

[Would you like to spend your lifespan to deduce martial arts?]

He poured all thirty-six years of his lifespan into the Evil-Slaying Blade Art in one go!

A flash of blade light, and the ape demon split in two from head to toe, its innards spilling across the ground.

One strike.

Just one strike.

But the price was that he had only thirty-one days left to live.

Slaying demons lets him absorb their lifespans? He can deduce martial arts, but not extend his own life?

Then he'll kill! Kill until they're all dead!