Build-Divide -#000000- Code Black

In Neo Kyoto, the citizens rely on the AR game called Build Divide to determine their socioeconomic status; Teruto Kurabe saves Sakura Banka using a mysterious card in his possession, and she enlists his support to help challenge the King.

Hiyori pleads to become Teruto's disciple, and follows Teruto and Sakura around; Teruto is pulled into a crowd of protestors and gets separated from Sakura and Hiyori; a young man named Naomitsu Enjo appears and helps Teruto.

One day, while Teruto is resting in his tent, an injured Naomitsu collapses in front of him. Sakura asks him what happened, and he explains that he just battled Dairo Keisen, also known as the “Card Professor,” who is a researcher of Witchcraft Medicine. Naomitsu fought Keisen because he heard rumors that Keisen was involved in dangerous human experiments and that someone powerful was supporting his shady activities. With each member having their own intentions, Teruto and his team embark on a journey to battle Keisen.

A virtual beach called the Kamitoba Beach Resort has opened in Neo Kyoto; Hiyori wants to go to the beach because she has never experienced one in real life.

Sakura challenges the King; she challenges Kikka so as to regain her own body; unable to take part in Rebuild Battles on her own, she tricks Teruto into fighting the battles that are needed to complete the key and appear before the King.

After Sakura's battle ends, Teruto announces that it is his turn to face Kikka; Kikka is overcome with joy when Teruto says that this is no longer a Rebuild Battle, but a fight between brother and sister.