The Dark Side of Aincrad

This is a fanfiction based on Sword Art Online:
Asuna is being forced to take a break from the guild The Knights of the Blood Oath and upon her temporary leave she notices a servant of the guild who has an ambition to join the guild properly and become a skilled swordsman. This is the story of what happened when Asuna and this mysterious servant go on a quest together, with an old "friend" of Asuna's tagging along.