Nube is confronted with various questions, each presenting an ethical dilemma, by a monster he meets in his dream. Nube is unable to provide answers to those questions and is attacked while his psychic abilities are suppressed. Then, in reality, Nube suffers the same wounds.
One morning, a huge ground painting of the Mona Lisa appears in the schoolyard of Domori High School. A student claims that it is the work of a yokai, and that creates an uproar.
Zekki, the younger brother of Baki, transfers into Nube's class disguised as a human. Zekki's purpose is to free his brother from Nube's left hand.
The battle between Nube and Zekki leads to the breaking of the Baki's seal. Having lost the demon hand, Nube decides to fight Baki without relying on the hand.
