The 4th feature tour installment. With Toi as the main host and Ryui as the subhost, the team heads to Aomori, the prefecture previously thought to have clues that may lead to the execution of Astaroth.
In between their research trip to snowy Aomori, they take time to search for Miura Morozumi, a spirit lawyer and Ryui's previous mentor. Meanwhile, Toi starts to realize that the rate at which he and Astaroth are assimilating is increasing at an alarming pace.
Knowing that he's slowly turning into the being whom Ryui hates more than anyone else, Toi tries to hide this fact from his brother, but his irreversible transformation may lead to more…