Sword Art Online: Aincrad, Vol. 2 (manga‪)‬

Sword Art Online, the world's first VRMMORPG (Virtual Reality Massively Multiplayer Online Role Playing Game), may have started out as a game, but it has since become a matter of life and death for the ten thousand players trapped within. Two years after game programmer Akihiko Kayaba's chilling declaration--"This might be a game, but it's not something you play"--the number of players has dwindled to six thousand, and for many, every day is a struggle for survival. Though Kirito has stayed alive by making a name for himself as a solo adventurer in that time, his life undergoes a major change when he unwittingly joins Asuna's powerful guild, the Knights of the Blood. What does fate have in store for Kirito, Asuna, and the brave young fighters who are risking their lives to return to the real world?!