Ixion Saga DT

Kon is a normal teenage boy who is spends his time playing a MMRPG where he is going nowhere, that is, until a girl in the game asks him for his help in the "real world" and he agrees. Then he does go somewhere - where, he isn't sure, but it is a fantasy setting much like the game, though nothing looks familiar. He saves a princess and her followers upon his arrival from the sky, when he lands squarely upon the leader of the group threatening them. He ends up joining the princess's group as he searches for a way back to his own world.

Synopsis from Anime News Network