Nishimura Taichi and Azuma Rin were normal high school students before the light of a magic circle enveloped them after they dodged a speeding bicycle on the way to school. When the two next awake they find an unfamiliar land with forests and open fields of grass. While they're both confused by the sudden turn of events, things take another turn for the worse as a huge horse with a sharp horn on its head attacks them...

After safely qualifying to become adventurers Taichi and Rin begin working out of the inn, Mithril, completing the easiest E-Rank quests. Then one day the guild makes its decision to directly entrust them with a difficult quest, holding high hopes for their abilities. The quest is one that D-Rank adventurers have already failed twice - the investigation of a smuggling operation in the slums.

Lately there has been a string of thefts targeting Azpire's local specialty - melila fruit. As a result, prices within the city are steadily skyrocketing. Taichi and the others accept a quest to guard the melila orchards, but when the monsters attacking the fields prove to be monsters that don't live in that region, they begin to suspect that someone else is responsible for setting up the attacks. Shortly thereafter a new threat begins closing in on Rin and Taichi.

Taichi manages to defeat the Red Element with the power of the wind spirit, Aerial. So when he speaks to Lemia about hearing the spirit's voice and using her power, she pronounces him a Summoner. While he feels like that power is just another cheat, he heads into the city to find Rin and Muller. Along the way he rescues a woman being harrassed by some men, but that woman seems familiar somehow...

After defeating the golem beneath Azpire Taichi and Anastasia encounter the young magicians Milo and Melo, who command a large horde of Red Goblins. Meanwhile Rin and Muller alert the guild to an impending attack from an army of several thousand monsters. A dour mood hangs over everyone there, but Rin and Muller resolve to defend the city. Luckily that's when Lemia arrives, having sensed something wrong within the city...

After wiping out the Red Goblins beneath the city, Taichi races to the battlefield and gallantly appears in time to rescue Rin. With his aid the adventurers of Azpire continue past their exhaustion to defeat the monsters one after another. While Taichi faces down the Red Ogres with his physical enhancement, Milo and Melo join them in the counterattack.

After overcoming the monster assault Taichi and the others are visited by a messenger from the Royal Family. Alsena, the emissary acting on behalf of Gilmar, King of Elistain Magic Kingdom, asks for their help. The Royal Capital, Wennifix, is currently divided between those supporting the King who's put great effort into diplomacy and those supporting his younger brother who opposes him. With tensions so high, a civil war is imminent.

Word reaches the Royal Capital that the King's younger brother has finally reading his troops for an attack. As the battle draws closer minute by minute, Taichi tries to convince Rin to stay away from the battlefield, yet she displays her strong resolution to fight alongside him. After learning of Rin's resolve he vows to himself that he will protect her.

After driving off the army of the King's younger brother, King Gilmar rewards Taichi and the others are with weapons from the royal treasury. Taichi, Rin, and Muller head down to the training grounds to test out their new weapons. However, Taichi grows ill along the way and goes downton by himself to buy some medicine. There he encounters Cassim, set on revenge, who forces him to accept a duel...

The King's brother, Dortesheim has declared war on Elistain Magic Kingdom, and finally waged a formal battle on the plains of Marwalt. The Kingdom has dispatched its soldiers against them, accompanied by Taichi and the others. Rin, Muller, and Lemia all face their own battles against strong opponents, while Taichi storms the enemy's main camp and takes action to end the war. Yet during the intense battle, the Kingdom's Cardinal, Lodra, is meeting with a mysterious person in the cathedral...

The tragedy of the "Bloody Rhapsody" - the worst battle in the history of the world - is about to befall the world once more. With dark magic turning the soldiers into berserkers who can't distinguish friend from foe, both armies begin advancing on the royal capital to slaughter it and everything that lies beyond. Faced with countless berserkers, Taichi is forced to make a decision. He finally resolves to use his power that's too great for one man in order to protect those precious to him, but...