Yorunami has long, wavy azure blue hair that reaches toward his legs and azure blue eyes. His clothing pretty much resembles Japanese sokutai traditional clothing. He wears a robe, that has a Shinshou mark on the center of his chest, and a fabric that wraps around his waist, which has his own mark located on it. He wears a separate lace on both of his arms, leaving an opening on his shoulders. This also has a Shinshou mark on it. Inside his robe, he wears a blue top and black leggings. He has his hair folded in and out and a pin attached to it. He has a bow on top of his head that reaches to his shoulders and another bow with beads on it that is located in the center of his chest. He has water droplet tattoos on both upper and lower portions of his eyes. To Hinohara's and Kannagi's point of view, Yorunami's appearance looks feminine.
Ever since Yorunami was a child, he had a desire to gain praise from his mother, which the desire continued into his adulthood. After his mother's death, he had became a ruthless, strict man and quite abusive towards his Zokushou. He showed no mercy whatsoever and simply despise savage, indecency, especially failure from his Zokushou when it comes to suppress his mother. Due to his behavior, most of the other Shinshou think his actions are foolish and laughable. His Zokushou still follow Yorunami, but are bitter about his demand for perfection. Even before his time as a Shinshou, he's willing to do anything to live up to his mother's expectation. After Arata Hinohara beats him in a duel, he discovers his mother had praised him all along. He finally calms and willingly submits to Hinohara.
Yorunami has always wanted to reaches his mother's expectation as a child. His mother wanted him to train martial art perfectly after his father passed away; his mother forbidden Yorunami to come close to her room. As a adult Yorunami didn't master his martial art completely as his mother told him to do so, and that time his mother died without praising him. He became lifeless when she passed away, but after that he changed completely and decide to continue train until his mother accept him.
He appears at the Himeou's ceremony, but not fully shown yet.
Yorunami is seen watched the events of Hinohara and company traveling throughout his kingdom from within his palace from the previous arcs. He kept tabs through his Zokushou, Hiruko, who was under a false alibi at the time. After Hiruko loses to Hinohara, Yorunami finally decides to get involved.
The Shou waits until Hinohara is conversing with the men to kidnap Kotoha as bait to lure the teenager within his palace. When Hinohara arrives, Yorunami has trapped Kotoha within a water crystal that will continue filling up until Hinohara submits, thus drowning her. Yorunami thinks his plan will prove successful and grows more assured when he traps Hinohara within another water prison. Except within this prison, he forces Hinohara to continue aging backwards in a trance and through hallucinations tries to manipulate Hinohara into submitting by pretending to be his mother. But he is surprised when Hinohara continues to refuse saying the word because in his mind all children wish to please their mothers.
Hinohara manages to wake up from the trance and saves Kotoha when she is close to drowning. Yorunami is astonished by the turn of events, but quickly grows frantic and runs away from the battle yelling for his mother to forgive him. Hinohara and Kannagi stumble upon Yorunami frighteningly clinging on to a set of robes which he keeps calling mother as he suffers from delusions. When Yorunami snaps out of the trance, he laments over his entire reason for living was to earn praise from his mother remembering his own past.
In anguish, Yorunami pretended she was still alive because he couldn't cope with the thought of her not ever appraising him. Hinohara quietly listens in and notices towards the end something peculiar hidden among the robes. When he tells Yorunami to check it out, the young man discovers a gift he had given his mother years prior that he had handcrafted himself. His mother claimed the thing was mediocre and dismissed it much to his sadness. In the end, he discovers she had kept the gift on her at all times and the treasure she cherished was in fact her son himself. After finally realizing he was his mother's treasure after all these years of questioning her love towards him, Yorunami breaks down sobbing with Hinohara and company watching quietly. As Kadowaki descends from the sky for a decisive match, Yorunami gifts Hinohara the power of water, finally that allows Hinohara to use a offensive move other than barricade. After Kadowaki's retreat, Hiruko and his followers then submit their power to Hinohara putting their faith in him.
Nakisawa (哭多, Nakisawa) a Japanese war fan
- Yorunami's Shinshou status are 252 years and his favorite food are vegetarian.