Synopsis: Demon Slayer's Quest

"My revenge will only end when I exterminate the demons." Lee Se is a boy ostracized as a monster in his village after brutally beheading the demon that killed his parents. Having lost all attachment to life, Lee Se meets Mong-ryeon, a goblin and demon hunter, and sets out to eradicate demons from the world. Thus begins his life with Mong-ryeon. During this time, Mong-ryeon discovers a certain "singularity" in Lee Se. To help him, Mong-ryeon sends him to the Daemudo, a sect of butchers in the cultivation world...