Cheonmanim Cheonhareul Dwijibeo Noeusyeotda

Abandoned by the Heavenly Demon, the ruler of all demons, Dokgo Yeon-Mi takes in Dokgo Cheon, a baby resembling the heavens themselves. As they attempt to live the life of the Dokgo clan, unconnected to either the Heavenly Demon or the Divine Cult, the Heavenly Demon reappears before them. Due to a twist of fate, Dokgo Yeon-Mi is destined to become a priestess, and to protect her, Dokgo Cheon devotes himself to the Divine Cult... 'If the Heavenly Demon stands in my way, I will become the Heavenly Demon!' Dokgo Cheon's sword begins to cleave the world against the Heavenly Demon who shattered his peace! (Source: KakaoPage, translated)