バクの新たな使命は、宿敵ノックスを倒すこと。夢の中でブラックホールをさまよいながら、バクは幼少期に見た悪夢を追うようになる。
幼いバクは予備校に通う。彼の行動を追うように、塾講師のノックスが現れる！ノックスとの過去の出会いに衝撃を受けたバクは、消された記憶を取り戻そうと、ノックスと対峙する！
Baku's new mission is to defeat his nemesis, Nox. Wandering through a black hole in his dreams, Baku begins to chase the nightmares he had as a child.
As a young boy, Baku attends cram school. His teacher, Nox, appears, as if pursuing his actions! Shocked by his past encounter with Nox, Baku confronts Nox in an attempt to recover his erased memories!
Enquanto Fujimi e Nasuka seguem à procura de Odaka, Baku recebe uma nova missão que traz consigo uma pergunta: ""Quem é o inimigo que deve ser eliminado?"".
Quando a noite substitui o dia, chega a hora de descobrir qual é o pesadelo do qual um certo alguém não consegue acordar...
