vactum

Yukiteru "Yuki" Amano is a loner who spends most of his time writing a diary on his cell phone or talking with his imaginary friends Deus Ex Machina, the God of Time and Space; and Murmur, Deus' servant. One day, Deus gives Yuki a special diary, mentioning something about a game.

Sora and Shiro are a pair of siblings, brother and sister, who are well known as brilliant. Yet they are NEETs - useless to society, and (Not in Education, Employment, or Training) - and even worse they are completely house-locked shut-ins (hikikomori!

In the year 2022, the gaming industry has reached a new height after the development of the NerveGear, a helmet-like controller that allows the user to fully dive their senses into the world of virtual reality. After a closed beta with only 1,000 testers, the Virtual Reality MMORPG Sword Art Online is launched.