Reverberation

Inside the Umesato Junior School Network, two girls are trapped and attacked by a mysterious avatar who strips them of their clothes and items. In the following day, after learning from Yuniko that the same phenomena is occurring at other schools, Kuroyukihime assembles the other members of Nega Nebulus and together they come with a plan to lure the perpetrator, with Kuroyukihime and Chiyu acting as baits while Taku and Haru watch over them in hiding. The plan works and the culprit, who is revealed as a girl named Dushka appears, but while confronting her, she draws the four to a special isolated low-gravity field. Kuroyukihime figures that the place is part of the Accelerated World and warns the others to activate their powers, transforming themselves into hybrids of their ordinary and Brain Burst avatars. While Chiyu fights the opponent alongside Taku, Haru transforms himself into wings for Kuroyukihime to use and defeat Dushka.