The Rise of the Unemployed Wise Man (Mangatoon) 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.nl fastest updating comic site. The Summary is

Karna, a boy who was given the mark of a sage by heaven, is scouted by the hero’s party for his talent. However, his talent for necromancy is seen as creepy and he is soon banished. Having received little reward and being left homeless, Karna accidentally enters the Demon King’s castle, where his life is threatened by a demon! The demon possesses great powers, but Karna defeats them with magic that far overwhelms them. The demon is terrified. Meanwhile, the Demon King Cecilia, who witnessed the whole thing, offers Karna a large annual salary. Thus, Karna decides to become an enemy of mankind as a magician employed by the Demon King’s army. The story of the unconscious cheat reversal of the unrivaled necromancy magician banished by the hero begins!