Rokka no Yuusha

According to an old myth, when the Demon God returns, the Goddess of Fate will choose six heroes, known as the Braves of the Six Flowers, and give them the ability to rebel against the demons who want to make the earth a living hell. Adlet Mayer, who calls himself the "Strongest Man in the World," has traveled to Piena in the hopes of joining the Braves. Adlet is welcomed by Nashetania Loei Piena Augustra, the crown princess and fellow Brave, though it doesn't go exactly as he had expected, and soon becomes one of the six heroes. Rokka no Yuusha follows the two as they set off on their predestined quest to battle the Demon God, with the goal of meeting up with their other heroes at a little temple outside the Land of the Howling Demons, the domain of the fiends. Seven heroes are present when they do unite, though, and the other heroes soon start to believe Adlet is a liar. Adlet is now on the run and must use his special talents and intelligence to find the group member who is the real impostor before it's too late.