Yasuki is very stoic, expressing little emotion and performing his tasks diligently. He is very protective of Mimane.
When Akito and Arumi Ashimine first entered Mayoiga, Yasuki fired arrows at them on site. Arumi was able to use her powers to predict his shots, helping Akito avoid his attacks. Their fight was interrupted by Mimane Miyou who excitedly and curiously approached the newcomers. Akito and Arumi were introduced to Tanmen and the other members of Mayoiga. Tanmen apologized on Yasuki's behalf, but when told to apologize himself, Yasuki remained silent. Yasuki would later apologize to Akito, stating Mimane getting too excited about the outside world whenever newcomers arrive as his reason.
Yasuki accompanied Akito, Arumi, Mimane, Chikage and Shinshou to capture the black mass that Arumi saw in her divination. After a few years in their capture, the mass would reveal itself as Azami. Azami gave them the information they required about a weakened god from whom they could take a Stone Shard from, providing them a plan to carry out their goals under the condition they follow her terms. Yasuki, Akito, Arumi and Mimane stationed themselves in Kamioka as per Azami's plan, going undercover at Kamioka East Middle School.
After the defeat of Mana Manaka's shoe amasogi, Mimane begins complaining about being bored and expresses disappointment in its defeat. Yasuki comments that Akito's plan was better than Arumi's. Mimane continues to complain and they eventually allow her to go forward with her own plan.
After the defeat of the pillow amasogi Mimane gave to Isuzu Iriha, Mimane begins complaining again, wanting to eliminate Kazuya Kagami and Kiriha herself. Azami attacks Mimane and Yasuki protects Mimane from Azami. Yasuki and Azami begin to fight, but they are stopped by Akito. Azami warns them to keep their promise and leaves. Yasuki asks Akito if they can trust Azami, to which Akito states they have no other choice and she has been correct so far.
After returning from the arcade with Mimane, Akito explains to Yasuki and Arumi that Mimane revealed her identity to Kazuya and Kiriha. Yasuki tells Akito he has gotten too relaxed. Some time later, Akito tells Yasuki that he has been blackmailed by Kiriha into joining her and Kazuya's club. After gaining approval to do so from Azami, Yasuki warns Akito of the danger os joining the club and to be watchful of Mimane's behavior. After their first day at the club and observing their target Kukuri in person, Akito tells Yasuki what happened. Yasuki asks about Mimane's whereabouts only for them to realize Mimane is not present.
Mimane returns, telling the three about an attack from other members of Mayoiga, who are identified as Genbu, Kyouka, Jungou and Senga. Yasuki suggests they should take the chance to strike and join them in the assault on Kukuri. Mimane tells them otherwise, telling them that Kukuri is still too powerful for all of them combined. They decide continue with Azami's plan and Akito and Mimane go out to fight against the Mayoiga invaders.
Yasuki, Akito, Arumi, Mimane and Azami return to Mayoiga where the see several smoking building in the distance. Upon their arrival, they are immediateley attacked by Sanjuurou. After killing Sanjuurou, Chikage comes to greet them and tells them to speak Tanmen to debrief them. Yasuki and Akito speak with Tanmen while the girls take a bath. Tanmen tells them that the radicals all revolted at once and committed the taboo of consuming humans to gain power.
Tanmen calls a meeting to have Arumi use her divination to decide their next action. After seeing two stone shards, Tanmen decides to reawaken Miurahi. Miurahi greets them all, and they announce Mayoiga will begin their full assault on Kukuri to kill her and claim her stone shard. Mayoiga launch their assault on Kamioka via a giant flying ship. Their ship is intercepted by a projection of Honoka. Creating an illusion of the ship, Miruahi sneaks ahead to Kamioka with a small group of tsukumogami while, Yasuki, Mimane and some others stay behind to keep Honoka distracted. Shien creates smoke platforms for Yasuki and Mimane to use as they battle in the air. Yasuki warns Honoka if she attempts to leave, they will begin interfering with the local exorcist and gods who are attempting to suppress aberrations caused by the increase in cursed created by their battle. As Yasuki battle's Honoka's projection, Mayoiga's ship suddenly reveals itself. Yasuki calls out to Mifune who tells them that Miurahi's power has disappeared and he can no longer maintain the ship. The ship collapses and the its passenger begin reverting back to their original forms as they fall. Honoka catches the falling tsukumogami and tells the remaining one to surrender since it is apparent that Miurahi has already died and they have already lost. Tanmen concedes and order Yasuki and the others to surrender.
Yasuki is taken to Tsuzura Temple along with the other Mayoiga tsukumogami, where they are held in storage. Yasuki is amongst the first group of tsukumogami rescued by Kazuya and Kyouka from Masuji Madarai's Servitude Faction. Yasuki is seen speaking with Mimane amongst the other rescued tsukumogami after she and the remaining Mayoiga tsukumogami are saved by Kazuya and Ouhi Oriobana in the aftermath of the Nine Masters Tournament.
As a longbow tsugumomo, Yasuki is capable of using bow and arrows as weapons. He is able to generate his own arrows with different arrowheads for different effects. Yasuki is capable of firing multiple arrows at once and altering their trajectory mid-shot.
Spirit Sewn Whistling Arrowhead: Fifth Arrow - Dazzling Scarlet Arrow (
|Leaders||Miurahi † • Tanmen|
|Members||Akito Ashimine • Arumi Ashimine • Azami ‡ • Chikage • Genbu • Guramon • Jungou • Kyouka • Mifune • Mimane Miyou • Rokkaku • Sanjou • Sanjuurou • Sarara • Senga • Shinobu • Shinshou • Sosogu • Tsuchishiro • Urara • Yasuki Yatsukawa|