Tales of a Shining Sword 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 talesofashinningsword.com fastest updating comic site. The Summary is

Eunho, the strongest in the youkai realm! He gained the chance to become a human being after losing the woman he loved and killing countless youkai. After passing the gate of reincarnation by accumulating merit for a thousand years to abandon his immortal body… He became a human being, held a sword, and learned martial arts for the first time. But this is very… easy?