I'm Not the Overlord! 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

I actually reincarnated into a different world and became the Demon King Overlord?! And my task is to destroy humanity! Wait, that ain't right. I'm a pacifist you know? I'm not like this at all? What? I killed a thousand human army with my energy blast?! That was an accident! It was the relic's fault! It's all a misunderstanding! Hahaha! Why can't we get along nicely? Huh? So what if I'm the devil? Doesn't mean I like doing bad things! Stop annoying me or I will blast you to kingdom come! Wait! Argh! Come on! I'm not that evil! I'm not the Overlord!