After the girls' research of Kuesu leads to them discovering that Kuesu's family rose to power as Demon Slayers using Western magic, Kuesu herself arrives to everyone's surprise, informing Yuto about their future marriage. Yuto, however, refuses to agree to it unless she can change her views about the Ayakashi. Following a brief scuffle between Kuesu and Rinko, Himari intervenes and mentions the three kisses she gave Yuto as well as the kiss she received from him to everyone's shock. Kuesu counters by telling them about the promise they have made, with Yuto clueless about what she is talking about. Later on after school, Himari faces off against Kuesu, gaining the upper hand with her agility. However, the battle is soon turned around when Kuesu starts to shoot Himari with her magic gun and casts a fire spell on the ground before Himari could attack, forcing her to use Yasutsuna as a step to escape the flames. Himari is soon hit by one of the bullets and quickly falls prey to its magic, causing her to go on a rampage. Just when she was about to kill Kuesu, she quickly remembers what Yuto had said to her back in Noihara and regains her sanity. Ashamed, Himari retreats from the battle, leaving a trembling Kuesu. Late at night, Yuto asks Shizuku where Himari has been and, after being told that she went off to fight Kuesu, an unconscious and beaten Himari appears in his bedroom to Yuto's shock.

During an art project at the park, Yuto is kidnapped by Ageha at a power station. While Himari and Rinko go out to search for him, Rinko gets a surprise visit from Sasa. Meanwhile at the water fountain, Taizo and the other students get a surprise visit from Shizuku, who wants to warn Himari of something. When Himari tells her about Yuto being kidnapped, they both prepare to look when they see a tired Rinko collapses with Sasa on her back. Himari demands Sasa of Yuto's whereabouts, eventually learning that he is with Ageha. Back at the power station, an excited Ageha drinks Yuto's blood and gets intoxicated after drinking it. Himari and Shizuku quickly intervene, both preparing to fight her but Ageha refuses, saying that someone is trying to kill off ayakashi in the west. Later, a man named Kaburagi from Public Safety's Section 4 appears, and after explaining to them about the numerous cases of an ayakashi comsuming other ayakashi, attempts to recruit Yuto into his division. Yuto, however, refuses when a mysterious blond-haired child appears in front of them. As Yuto and Himari run for the exit, they see a mysterious man blocking it and, after a failed series of attacks from Himari, Sasa, and Ageha, the blond-haired child attacks Himari and bites her, revealing she is the ayakashi who is killing other ayakashi. Kuesu later arrives at the scene, identifying the two as Tamamo-no-Mae and Shuten-doji, two of Japan's three strongest ayakashi. However, just as she was about to fight them, Tama and Shuten-doji vanish. Himari then recalls Tama's words from earlier, which leaves her worried.

The battle between Tama and Himari intensifies with Himari transforming to her ayakashi form. Yuto and the other girls soon arrive at the battle scene and they are shocked at Himari's transformed appearance. Tama soon assumes her fox form with Himari in her jaws, but Himari breaks free and deals a powerful blow to her, defeating her. However, after Yuto and the girls come down to see Himari, Himari, having lost all sense of reason, attacks them and eventually beats them, leaving Yuto the only one left. Yuto then resorts to killing Himari with the latter's Yasutsuna, but drops it at the last minute and hugs Himari, telling her to come back to him. After returning to normal, Himari and Yuto prepare to fight an enraged Shuten-doji in his oni form, where Yuto then imbues Himari's Yasutsuna with his Light Ferry ability. Using her newfound power, Himari defeats Shuten-doji for good, with a hungry Tama emerging from the rubble soon after. Following the fight, Kuesu asks Yuto to use his Light Ferry ability to fix her clothes, but could not do so to his surprise. The next day, Yuto gets an angry visit from Kisaragi, Taizo, and the Class Rep, which later leads to a misunderstanding after seeing all of the girls in his house.