Kirigaya Minetaka and Midori, husband and wife’s own child was Suguha, while Kazuto was Midori’s sister’s, this meant that he was the child of Suguha’s aunt. Her aunt and her husband, without a choice, left their only child, who was not even a year old, and passed away in an accident. The serious nature of the injuries they bared eventually putting an end to their lives, and Midori was left to take charge of Kazuto. That fact was told to Suguha by both her parents during winter two years ago, around that time, Kazuto was trapped in a virtual reality game, going by the name of «Sword Art Online». Suguha who had already received a big shock from the incident, was in a cruel state of confusion; she went to Midori, asking why she did not tell her earlier and why she was the only one not being told, and took out her confusion on Midori. Two years had passed, and even now within the bottom of her heart, the feeling of alienation was lurking, of being the only one who did not know anything. However, during this time she had finally come to understand her parents’ feelings at that time. Their original plan, of informing Suguha of the truth after she entered high school, had been hastened, in short, she was told everything of the truth of her family while Kazuto was still alive, which was the bitter decision both her parents made. Within a month’s time of the outbreak of the SAO incident, there was an absurd number of 2000 deaths. Under those circumstances, the both of them could not help but make a compulsory resolution for Kazuto’s certain death. At least after everything was over, they would not regret that Suguha «did not know it», which was what both her parents must have certainly thought.