The Heavenly Demon Wants a Quiet Life is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

."In my next life, I wish to walk a completely different path…" The Heavenly Demon, whose life revolved around fear and reverence, gained a crucial clue to mastering the Soul-Augmentation Art at the moment of his death: The "Soul-Augmentation Art" wasn't just about consuming the souls of others. The Heavenly Demon then awakened in the body of Byeok Taesan, a frail young noble who could die at any moment... To survive, he must make his way to the courtesan house! The Heavenly Demon, now transformed into the "Night King," begins his ambitious journey of survival.