Shiiho (椎, Shīho) is a shinki of Arahabaki. He also goes by the moniker Shiigun (椎軍, Shīgun) the Pestilence; this is most likely in reference to his vessel form, since the character 軍 means 'troops, battle'.
Shiiho has the appearance of a preteen boy. He has black hair and dark eyes. He wears a white kimono with black stripes over a black undershirt and leggings.
When he is first seen in his human form, he has a thin scar traversing diagonally across the right side of his forehead. However, it is not present the next time he appears; it most likely was a wound that had not yet finished healing after the subjugation of Bishamonten.
Shiiho has a boisterous, teasing personality around his master and friends. However, Shiiho seems much shyer and more awkward when around adults he doesn't know well, such as the Seven Gods of Fortune. He is protective of his master and somewhat combative. This is shown by how he yelled at Yato that he wouldn't lose to him again, but became much calmer and cheerier when Arahabaki assured him that Yato had not come to cause trouble. Shiiho also seems to be rather blunt or crass.
When Yato visits Arahabaki, Arahabaki tells Shiiho that Yukine wasn't with him, implying that Shiiho had wanted to meet the hafuri. Shiiho doesn't approach yet, but quietly says that it doesn't matter to him. He appears flustered when Arahabaki pulls him over to say hello, but then he adamantly states that he isn't going to lose to Yato again. His expression clears to confusion when Yato coos at him and asks him to befriend Yukine if they ever do meet. The other shinki present seem concerned that Yato may be their master's enemy since he had gone against the Heavens, but Arahabaki says that it's fine. Shiiho then appears much cheerier as he gathers everyone for lunch.
Shiiho explains to Nana the purpose of Ooharai, which he and Arahabaki would partake in together this year. He teases her for not being able to leave the mountain with them, and jokingly tells her not to sleep with her belly out before they leave.
Shiiho is seen with Arahabaki as gods gather to prepare for their departure for Ooharai. When they speak to the Seven Gods of Fortune (excluding Bishamonten, Ookuninushi, and Ebisu), Shiiho awkwardly introduces himself. Hotei is surprised that a small-spoken child is the one who transforms into Shiigun/Tsuiki, while Benzaiten coos that she finds him adorable, and Fukurokuju and Jurojin also welcome him kindly. Shiiho blatantly asks where Ebisu and Ookuninushi are, and then essentially says that the Gods of Fortune who are present are the less-important background characters, much to Arahabaki's distress.
Shiiho and Arahabaki are assigned to cleanse Bishamonten's patrol area. After Arahabki explains Shiigun's problem with borderlines, Benzaiten sends her shinki away with Shiigun. Murasaki asks Shiigun what he meant when he said that Ebisu and Ookuninushi aren't here.
Right before beginning their rounds for Ooharai, Arahabaki rides one of Shiiho's horses. Shiiho suggests that they try some of the local food. Arahabaki tells him they can just pick up souvenirs on their way back, but Shiiho bluntly says that he has bad taste in souvenirs. He excitedly says they stop by the bank, but they notice that strangely, there are no phantoms around. Shiiho wonders if there are only small ones in the area, but they're stopped by a thin tendril in the sky. Two people, presumably other gods who are making their rounds, are caught in the same tendrils. It appears that these tendrils are part of Hagusa's righteous net.
As a vessel, Shiiho takes the form of an army of men on horseback. Some of the men carry spears, which they can use as close-range or projectile weapons. Others carry swords or bows and arrows. They all chant the word "ohm" / "on" meaning "bane".
It is unclear how closely Shiiho is able to control each individual member of the army; thus far, Tsuiki has been shown to act almost like a swarm, all converging in one area. According to Yato, since Shiiho is split across so many parts, defeating one man or horse barely registers as a scratch to him.
Shiigun seems to be well-known for his strength, as he was called in as a last attempt to assist in killing Bishamon, who expressed worry at his presence. However, Arahabaki explains a draw back to Shiigun is that shinki that spread themselves too thin have more difficulty maintaining a borderline. Thus, they are at higher risk of damaging the Near Shore. Shiigun carries the second name "pestilence," which further worries Arahabaki that he may negatively affect plant life on the Near Shore if they are not careful.