Spin-off of Accel World included on the anime Blu-ray/DVDs.

Bundled with the limited editions of 17th, 18th, 19th, and 24th volumes of the Hoozuki no Reitetsu manga.

Jinto and Lafiel were riding on a light-armed transport ship Bokbrusue and navigating at the planar space of the Hyde System. This was for Jinto to govern the Hyde System, which returned to Empirial rule after the Union retreated, officially as an Earl. However, the government of Martin, Jinto`s motherland, resisted obstinately against the Empirial rule. On the other side, Daiichi Jyuurin Sentai (the First Devastation Fleet), formed with the new ship type Attack Vessel, travelled to the Hyde System for drilling practices, but... (Source: ANN)

Mysterious disappearances are occurring one after the other in Tatsumi Town. Kiriya has a vision from a mysterious beautiful girl with pointy ears. A book talking for an alternative world is found. And Mao searching for her long lost friend, Zero, comes to our world. But what she didn’t expect is to find Souma and Kureha, and even less, to accidentally take them to her world. Now, Souma and Kureha have to find a way to come back. But other forces are playing their part in the darkness and Souma with Kureha will find that going back is harder than they first anticipated. (Source: ANN)