OriginS is a Manga/Manhwa/Manhua in english language, Manhwa series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

Suijin is a bandit who has been expelled from the Gisha Walls along with two of his friends. They then live in a world where monsters are the bone of competition and battles with the walls troops are unavoidable. How's the story going? Let's read it.