Accel World, Vol. 6 (manga)

When Kuroyukihime returns from her school trip, she finds that Nega Nebulus has had quite the harrowing adventure in her absence, having been taken very much to task by a new threat--Dusk Taker! It seems, though, that the Black Legion has emerged stronger than ever and with two new members to boot! Could it be that they are ready to tackle a new challenge and take their adventures to the next frontier...?!