The office members help a love-stricken client track down the object of his affection, and Kabane learns a lesson about love. Akira decides to pattern himself after Kabane, and the two are assigned to investigate a deadly case on the Shibuya River.

When Akira runs away from the office over a trivial dispute, he unexpectedly bumps into his long-lost brother, Yui. Akira is delighted, but Yui behaves strangely, as little by little, the events of the past in their snowy home village are unraveled.

Kabane and the others try to bring Akira home from the ice castle, but are stopped by the power of Yui’s nullstone, and Akira is overcome with shock at the turn of events. Meanwhile, Inari and Nobimaru secretly go into action to claim the nullstone.

Nobimaru has a tough battle against Yui, who is using the power of the nullstone, until Kabane leaps in to help him. Kabane uses Nobimaru’s tactic and gives his all to beat Yui’s freezing power, as the battle over the nullstone finally reaches its climax!