The Privilege of the Second Life is Power Leveling

Ten years after humanity’s fall, Earth lies under demonian rule. After losing his sister and his life, Yoon is offered one last chance by an angel statue. Sent back in time with a leveling system, he must reach Lv. 99 to save her and change Earth’s fate. Yoon fights, not for the world, but for her. One brother’s journey to save his sister may be humanity’s last hope.

(Source: Tapas)