Izana Wistaria was the First Prince and is now the current King of Clarines. He is Zen's older brother and the fiancé of Haki. His parents are Haruto Wistaria and the late Kain Wistaria.
Izana is a handsome young man in his twenties. He has shoulder-length blond hair and dark blue eyes. Six years before the manga and currently, his hair is long and tied in a ponytail. As the First Prince of Clarines, he wears formal clothing while in the castle, especially when attending to official matters. His usual attire consists of a black long-sleeved collared shirt, a vest with ornate patterns along its edge and light-coloured pants. His sword is usually brought around with him, and he sometimes wears a jacket draped over his shoulders.
When in Lyrias, he tied his hair into a short ponytail. He wears a light-colored jacket with fur at the sleeves over a black collared shirt. He also wears a fur-lined cape or a jacket with fur at the collar and edges.
When he was the heir and then king of Clarines, Izana has demonstrated he is a responsible ruler who puts his people first. This can be seen from how he responded quickly in the Lyrias incident, ordering for Lyrias' gates to be barricaded so that the travelers entering and leaving the town would not spread the disease to the surrounding area. He also often leaves the castle to travel to various parts of the country, likely for official and important matters. He has no patience for kings who would exploit their own people, as demonstrated when he brought down the corrupt lords of Lido and Sui on his seventeenth birthday.
He is also a shrewd individual and can come off as very intimidating and manipulative when he wants to. This was demonstrated when he arranged to meet Shirayuki while holding official meetings with Zen when he deliberately revealed Shirayuki's presence in the meeting room, indicating that he was going to have a talk with her, before dismissing his younger brother. This frustrated Zen greatly, but he had no choice but to obey. After hearing of Shirayuki's history with Prince Raji, he also decided to invite Raji to the castle. Despite his usual serious demeanor, Izana also has a playful side, as he appears to enjoy teasing Zen about his feelings towards Shirayuki. When Mitsuhide confronted him about how he was testing Zen and Shirayuki, he smilingly tells Mitsuhide Rouen to stand next to him by the window, a movement that reveals to Zen who was walking outside that Izana and Mitsuhide had been talking in private. He then responds with a cheery "Oops, looks like our rendezvous has been discovered." and walks off. This incident naturally irritates Zen, which in turn made Mitsuhide a little flustered.
When he first returned to the castle, he did not inform Zen, who was away at the time, of his return. The castle guards were also presumably under orders to keep this information from Zen. When Zen confronted him about this, he simply said that he was testing how much attention Zen paid to the going-ons in the castle. When Izana set off for Lilias, he also did not tell Zen about where he was going even when Zen asked him.
Izana also has a tendency of concealing his identity from others during their first meeting, preferring to maintain some semblance of anonymity. This could be seen when he signaled to Ryuu not to tell Shirayuki about his identity, and also later when he took on the alias Rouen (which is Mitsuhide's name) while in Lyrias, claiming to be Garrack Gazelt's assistant in order to observe freely.
He is also shown to be both observant and nimble, being able to eavesdrop on Zen and Shirayuki's conversation without being detected. He later noticed Obi who was hidden in a tree and was able to catch Obi off guard, throwing a sharp stone that caused a cut on Obi's face and disappearing from sight immediately. He was also able to vanish from Mitsuhide's sight after turning a corner despite the fact that Mitsuhide was looking for him, and later surprised Mitsuhide by revealing that he was leaning against the wall just next to Mitsuhide all along. Izana has a tendency of appearing at unexpected moments, his presence completely unnoticed by others until he reveals it.
On his seventeenth birthday, he asked for a castle on the border of the Lido Territory and Sui Territory. This shocked the lords who were present, for the lord of these two territories have long been unable to get along. However, when asked whether he was going to resolve the conflict between the two, Izana said flippantly that it seemed like a nice place to build a castle. The two lords began competing for Izana's favour, sending money and goods which Izana accepted as construction funds. The situation deteriorated into one where the lords started exploiting the people for this cause. A retainer from each lord came to request Izana to stop this situation, but they were ignored. The court, looking on, viewed Izana in a bad light, thinking that he was manipulating the lords for his own benefit. Zen was unhappy about Izana's decisions, to which Izana decided to bring Zen with him on a visit to the new castle and the two competing lords. Izana remarked to each lord about the other's actions, saying that the other is foolish for extorting their people to bribe him. When the lords turned to illegal connections to obtain funds, Izana investigated those deeds and overthrew both lords. He named the two retainers who had come to him as their successors. All bribery given by the lords were returned to their respective lands. Later on, when Zen apologizes for believing that Izana had been playing around and wonders if the lords may hold a grudge, Izana calmly comments that they may come back to kill him in the future. He tells Zen that he must make people recognize him as their lord and establish his position. Zen then makes the resolution that he wants to become someone who can stand by his brother's side.
Six years prior to the manga, Izana visited the base of the Sereg knight group, where Mitsuhide was training, and witnessed Mitsuhide winning his sparring match. They later had a private talk. He had previously mentioned to Mitsuhide about wanting to have him work in the castle. His purpose of coming to the base was to bring Mitsuhide back with him to serve his younger brother. Mitsuhide is flustered by this, saying that he is still inexperienced. After Izana stated that Mitsuhide may serve Zen forever if they were compatible, Mitsuhide also expressed the wish to serve Izana one day, to which Izana looked disappointed and said he would find someone else to take the job. Mitsuhide then decides to accept the job and returns to the castle with Izana. While walking in the courtyard, Izana tells Mitsuhide to look up and they see Zen jumping overhead from one roof to another. Izana tells Zen to come down when he tries to hide. Izana introduces Zen to Mitsuhide.
When Mitsuhide comes to him for advice concerning Zen who would often sneak out to play with Atri, a young servant boy, Izana tells him to keep an eye on them. He suggests some places that the boys may frequent. Later, when Atri betrays Zen, Izana appears before the men who demanded an audience with him by using Zen as leverage. It is revealed that they represent the fallen Lido family whose lord was previously overthrown by Izana. Izana and Mitsuhide engaged in a battle with the men and defeated them.
One month later, Izana secretly watches from behind a pillar as Mitsuhide and Zen talk. Knowing that Mitsuhide has gained Zen's trust, he walks away, allowing them their private moment.
Haki is Izana's fiancée. She and Izana don't show their feelings openly like Zen Wistaria and Shirayuki but they are very fond of each other. It can be seen when Izana kept constantly looking back at her while leaving Lyrias . Haki was present during Izana's coronation and asked him to cut his hair like Zen's so people would be able to expressions in them. He asked her whether it was her fetish which she hotly denied. Izana then tells Haki it’s more convenient if his eyes can’t be seen that well and won’t be cutting it so she needs to get used to it.
Kain is Izana and Zen's father. Not much is known about their relationship.
Haruto is Izana and Zen's mother. She ruled Clarines untill Izana was crowned as King. She was present during Izana's coronation and a few days before. She seems to love her sons a lot. However, not much is known about their relationship.
Their relationship initially appeared to be quite cold, with Zen stating "I do not want to speak to that guy alone" as the reason for bringing his close aides along with him when he received a summon from Izana. Their conversations tend to be very guarded, at least on Zen's part. However, it later becomes more apparent that Izana is greatly respected by his younger brother Zen. This is particularly noticeable in their younger days, with Zen resolving to become someone who can stand by Izana. Even in the present day, Zen works hard to keep up with his brother. Izana has come to give more and more responsibility to Zen as he matures, trusting him with several matters regarding the rule of the country. While Izana is initially disapproving of Zen's relationship with Shirayuki, he eventually accepts it and even gives his support.
In his youth, Mitsuhide originally aspired to serve Izana, but Izana gave him the task of being Zen's aide, saying that he was most suited for the position. In the early days as Zen's aide, he went to Izana for advice. Mitsuhide's attitude towards Izana when not dealing with official matters is generally respectful but still quite relaxed. He dares to speak his mind regarding some matters to Izana. Izana once remarked that like Zen, Mitsuhide had gotten "quite cheeky" over the years.
When Shirayuki referred to him as "Zen's brother", Izana appeared to be amused, saying that he doesn't often hear people address him as such. At the beginning, he deliberately attempted to intimidate and discomfort Shirayuki after hearing of her close relationship with Zen, even to the point of kissing her. Izana's provocation led Shirayuki to become insecure about her position by Zen's side. But after Shirayuki's resolve strengthens again, she dares to stand up against Izana, stating clearly that she has no intention of returning to Tanbarun and that she will remain in Clarines. She becomes less afraid of him as time passes.
- "She called me Zen's brother. That alone was interesting enough." —To unknown noble regarding Shirayuki.
- "What strange kids you two are." —To Shirayuki regarding her's and Zen's resolution.
- "Zen, what was the one thing I told you to remember about that girl? The colour of her eyes. When she returns to this castle, it would be good if it's cloudy." —To Zen regarding Shirayuki's leaving for the Tanbarun night ball.
- "Right here, right now, would I ignore the words of a palace pharmacist?" —To Shirayuki in Lyrias.
- Much like Zen, Izana enjoys going laying low and acting as a civilian to better understand the current situation.
- It is thought that Izana is 6 years older than Zen.
- He bares a strong resemblance to Howl from Howl's Moving Castle.
- Izana was ranked seventh in a character poll.