Ochikobore Eji Minarai no Shounen. (Jitsu wa) Saikyou Saiaku no Asashin. 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 a certain kingdom’s capital, war is approaching. A young boy named Il, an apprentice guard, is treated as a useless person who can’t do his job properly, living a lazy life while constantly relying on his stepsister.