Thor, Narukami-kun
Actually the Norse God of thunder Thor in the form of a teenage boy with brown hair and eyes. He was sent to Earth from the realm of gods to kill Loki in the manga he doesnt remember this at first while in the anime he chooses not to kill Loki because he sees no reason to. Unfortunately he forgot how to return to the realm of the gods so he is forced to work a wide array of parttime jobs to support himself which becomes another one of the series recurring jokes. He always carries around a wooden sword which is actually Thors hammer Mjollnir in disguise. Source: Wikipedia