While cleaning in the school, Asako and some other girls get trapped by a Stone Eater yokai.

Ushio demands his mother's whereabouts from his father, who promptly escapes. After Shigure reports about Ushio, the Beast Spear and Tora to higher ups, he is asked to monitor both Ushio and Tora to see their worth. When they are attacked, Shigure deems Ushio and Tora to be worthy and gives money to Ushio to go meet his uncle, and learn more about his mother from the journey.

After escaping the attacking youkai and saving an old man, Ushio recovers his strength and rests at a bakery in a small town. Ushio relates to them his struggles and how many people have been endangered since he pulled the spear. Ushio is reunited with the Kamaitachi siblings and the team tries to resist the youkai forces. They are saved by Tora and escape. However, a mist warps Ushio to a humble mansion of the leader of the mountain youkai. The leader relates the remainder of the tale of why the youkai seek vengeance against Ushio. His mother is part of a line of women tasked with upholding a barrier keeping Hakumen no Mono dormant yet preventing the other youkai from exacting their revenge on the monster. After Tora battles Hitotsuki, all the youkai cede and allow Ushio to continue his journey.

Once inside the cave, Ushio and Tora are carried over to the past by a time manipulating yōkai. There, they bear witness to how Hakumen no Mono first attacked the king and people of China, destroying the city and killing the parents of Jie Mei and Giryō.

Another morning fighting with Tora followed by going to school with Asako. However, an organization named HAMMR breaks the usual cycle. The three mad scientists of HAMMR kidnap Ushio and Asako and Tora go after them in an attempt to save him.

After being tricked by Hakumen no Mono, the JASDF prepare to send subs to destroy the stone pillar where Ushio's mother is, as she keeps Hakumen sealed. Ushio heads to Okinawa to stop them, but runs into Nagare, who seems to have switched sides. Ushio leaves Nagare to Tora, and hurries to stop the subs. Nagare and Tora go all out in battle, and Asako finds out a secret about Ushio...

Hakumen crushes its eyes itself to overcome the fear of the Beast Spear. Tora wants to save all the people even if it has to sacrifice itself, and tells the strategy to Ushio.