Lifespan Deduction System: Invincible Demon Slayer

In a demon-infested world where humans are prey, martial artists sacrifice their own lifespan to master devastating techniques. Shen Lin, a lowly constable with no backing, awakens the Life-Spending System—turning the tables by devouring demon lifespans to fuel his cultivation! Watch as he evolves basic skills into apocalyptic powers: from Blood Battle Saber to the world-splitting Blood Sea technique, from Golden Bell Shield to the Great Sun Demon-Burning Golden Body. The ancient demon lords who feast on humanity are about to meet their executioner.