GodKilling Ore-sama Saikyou Tenshi no Shinkatan

Lucifer is an angel who enjoys combat and refuses to lose. During a fight with the Demon Lord, he is betrayed by his allies and transported hundreds of years into the future, landing in a modern era where demons and humans live together. Stripped of his powers, he discovers a new method of growth—by defeating opponents, he can copy their abilities. He understands that defeating more enemies increases his strength. Now, he actively searches for and challenges the strongest foes he can find.