Jeonjijeok Dokja Sijeom

Back then, Dok-Ja had no idea. He had no idea his favorite web novel 'Three Ways to Survive the Apocalypse' was going to come to life, and that he would become the only person to know how the world was going to end. He also had no idea he would end up becoming the protagonist of this novel-turned-reality. Now, Dok-Ja will go on a journey to change the course of the story and save humankind once and for all.
(Source: WEBTOONS, edited)