‘Zero no Tsukaima: Futatsuki no Kishi’
Hiraga Saito, just your average high-schooler, had just picked up his laptop from getting repaired, as a portal of some kind opened in front of him. Saito’s curiosity getting the better of him, he touched it and was sucked through. At first, Saito had no idea where he was, and was thoroughly disoriented. By accident he was summoned to another world by Louise Françoise le Blanc de la Vallière, nicknamed “Zero Louise”, a magician in training whose only ability was it to blow things up.
It turned out that she was in the process of summoning a familar when he appeared instead. In this world where only the nobility is able to use magic and everybody else belongs to the common folk, it was unheard before that a commoner became a familar to a noble. They had to obey the rules though and Saito became Louise’s familar while searching for a way back to his own world.
As Saito became accustomed to his new surroundings, he found out that in this world he had the powers of a Gandalfr, being able to use any weapon at will, while Louise had the power of void, the legendary lost fifth element. Together they helped Princess Henrietta of Tristania to fight off the invading Albion forces which came at a great cost.”
Descriptions taken from AniDB.net