Even two months after he had been logged out of SAO, Kazuto continues to be plagued with nightmares about Asuna. It is also revealed that throughout his two-year coma in the game, his younger cousin, Suguha, has been constantly worrying about him. The pair have a kendo spar, and though Kazuto loses, Suguha is both shocked and curious about his unusual yet proficient sword fighting skills -- a result of his time in SAO. Later, Kazuto goes to the hospital to visit Asuna who, along with 300 other players, has yet to wake up even after the SAO incident. It is there that he meets an associate of Asuna's father, Noboyuki Sugou, who reveals to Kazuto that he intends to be adopted into Asuna's family while she is still comatose as a precursor to marriage, much to Kazuto's fury. Claiming this as his right since that it was his company that had been keeping Asuna alive after SAO's developer went bankrupt, he informs Kazuto that the ceremony will occur in a week and tells him not to see her again. Later at home, Kazuto breaks down before Suguha, who tells him not to give up, despite harboring her own feelings for him. The next morning, Kazuto receives an e-mail from Egil with a screenshot of an avatar resembling Asuna from another game.
In the near future, a Virtual Reality Massive Multiplayer Online Role-Playing Game (VRMMORPG) called Sword Art Online has been released where players control their avatars with their bodies using a piece of technology called Nerve Gear. One day, players discover they cannot log out, as the game creator is holding them captive unless they reach the 100th floor of the game's tower and defeat the final boss. However, if they die in the game, they die in real life. Their struggle for survival starts now...