Tsurara Oikawa (及川 氷麗, Oikawa Tsurara), often called Yuki Onna (雪女; Literally meaning "Snow Woman"), is Rikuo's trusted attendant and part of his new "Hyakki Yakō" who follows him to school under a human guise known as Tsurara Oikawa. Around the Nura House, she sometimes acts as a cook - making delicious but usually chilled or cold food.
Tsurara has long hair colored a mix of black, blue, and white with two wavy black horizontal lines along one side of her head. Her eyes are large and amber, with multiple rings inside them. She is most often seen wearing a scarf with vertical zigzag stripes and a furisode with a snowflake pattern along the hem and the bottom of the sleeves. As the sleeves are rather long, she can tie them back at the shoulders to provide greater freedom of movement during battle. When in her human guise as Tsurara Oikawa, she wears the Ukiyoe Middle School uniform as well as a scarf. Her hair looks about the same, but her eyes are blue.
A cheerful and dedicated yōkai, she is the same age as Rikuo. Tsurara is overprotective of Rikuo in both his forms, though far more so when he is in his "day" form. She does not want to be a burden to him and has stated she will protect him for all eternity, as he was the one with whom she exchanged sakazuki. She shows great admiration for Rikuo's "night" form, finding him reliable and magnificent. At first, she is fearful of Yura for being an onmyōji, but once the latter discovers that Tsurara and Rikuo are actually yōkai, this changes and they eventually come to tolerate and rely on each other.
She is increasingly affectionate toward Rikuo as the series progresses, seeing a rival in Kana and suggesting on several occasions that a problem could be solved by freezing her. Despite this, she will still protect Kana as her death would make Rikuo sad. Tsurara also has bouts of jealousy when other women are close to Rikuo, such as when Kejōrō embraced him while assigned as an extra guard. On several occasions, other characters express how bad a situation would become if Tsurara were to see other female characters being affectionate and/or overly friendly with him.
Tsurara has been looking after Rikuo since he was young, often ending up falling for his various pranks. Four years ago, she was among the yōkai who accompanied him to rescue the school bus and ended up fighting members of the Gagoze Alliance. Since then, she has attended school as Tsurara in order to watch over and protect him. She does not seem to have been a member of Rihan's Hyakki Yakō.
During the Gyūki Arc, she came along with Rikuo in order to watch over him when Kiyotsugu announced that they were going to Mount Nejireme. While the girls are in the onsen, she, Rikuo, Kiyotsugu and Shima set off to look for spirits. Meanwhile, they were being watched by Gyuki's minions, who had been ordered to kill them. She was separated with the three of them and encountered one of Gyūki's subordinates, Gozumaru. She was defeated but was saved by Rikuo who then fought against him and won. Rikuo then put her to sleep and left her to Kana whom he encountered while on his way to find Gyuki.
In the final battle against Tamazuki, Yosuzume takes Rikuo by surprise and touches him once, blinding him. Meanwhile, Tsurara is hurriedly searching for him while the battle takes place. Even though Rikuo is unable to see, he was able to fend off Tamazuki's underlings long enough for Tsurara to appear to his aid. Just as he is about to be killed, Tsurara blocks Tamazuki's attack with her staff. Yosuzume then blinds her as well, despite her attempts to try and cover her eyes.
It is later revealed that Tsurara had frozen her left eye over before the feather could reach it and had been able to see for the entire time. She waited until an opportunity presented itself and eventually froze Yosuzume when her guard was down. The poison then wears off and Rikuo prepares to fight Tamazuki once more.
Tsurara did not make many appearances during the Toono Arc, but she was mentioned at the beginning by Rikuo while he was doing the laundry about how she was always happy to do it for him. She also wrote several letters to him, most of them concerning about his health and well being.
She had to stay with Aotabō with the rest of the Kiyojuji Paranormal Investigation squad at the Keikan house headquarters. She then later finds Rikuo during his battle against Tsuchigumo where Rikuo and most of his Hyakko Yakō were promptly beaten by Tsuchigumo and she is taken as bait for Rikuo to go after Tsuchigumo. Later once she was free, she preforms Matoi with Rikuo and they freeze and shatter one of Tsuchigumo's arms. As Tsuchigumo keeps attacking, Rikou attempts Matoi with her once more, however she "politely declines" (arguably because of jealousy that Matoi can be performed with anybody and not just her as she initially thought) making Rikuo to perform Matoi with Itaku.
After Tsuchigumo was defeated she follows Rikuo in an all-out attack against Hagoromo Gitsune's stronghold and are met by Kidōmaru. Rikou once more attempts Matoi with her, but Kidōmaru knows the technique and easily cuts their fear, and Rikou then performs Matoi with Kurotabo, she's then seen fighting Hagoromo Gitsune's forces until the revival of the Nue.
Four months after the revival of Nue and Rikuo's ascension to power as the 3rd heir of the Nura Clan. Tsurara has been promoted to a high-ranking position and entrusted the Nishikigoi district, which was formerly ruled by her mother, with the intent to gather more allies into the Nura Clan for the battle against Nue. She then tries to get the Arawashi Family, a clan of stall-keepers and yakuza who provide financial backing for the Nura Clan under her wing, but is immediately rejected by them seeing nothing more than a girl in her. She's promptly teased by Gozumaru and Mezumaru for her incompetence as a commander. She eventually runs into the Kiyo Cross Supernatural Squad, who is looking for Tsukumogami and later departs. After this she buys a pot for shaved ice, which when poured with her ice, turns into a Tsukumogami called Onryu. Being called master by her she then proceeds to buy many old pots with the intent of creating of Tsukumogami's who are sworn to follow her. Although reluctant of the results she's nonetheless happy that she managed to get allies of her own.
Later she attempts to earn the sympathy of the Arawashi Family by working with her new followers, and they prove themselves fairly competent workers and over time are better received by the family. During a day of work customers of the clan are attacked by Tsukumogamis more sinister than Tsurara's and she launches herself at the enemy defending humans and part of the Arawashi Family alike. Facing the large fusion of Tsukumogami, she's backed up by the Arawashi Family, where they fight and defeat the Tskumogamis and the Ayakashi controlling them. With this proof of courage she earns the respect of the Ayakashi Family who proceed to tell her of the hardships they faced with the Hyaku Monogatari Clan, and how Setsura and Rihan were of essential support to keep their business. They then accept her as leader, who in tells them to follow Rikuo. While they don't know much about him, they nonetheless willingly accept to aid him given Tsurara has great faith on him.
Her "fear" is the ability to manipulate ice and cold wind, which primarily enables her to release a long breath of snowstorm that can freeze her opponent. Her ice techniques allows her to model weapons like the naginata and items like the skateboard.
- Noroi no Fubuki, Yukigeshō (呪いの吹雪・雪化粧) is a technique that freezes and shatters the enemy to pieces.
- Noroi no Fubuki, Fūsei Kakurei (呪いの吹雪・風声鶴麗) is a technique that creates a strong blizzard and freezes the enemy.
- Noroi no Fubuki, Yukiyama-goroshi (呪いの吹雪・雪山殺し) is a technique where Tsurara blows out cold air which makes her target sleepy.
They know each other since Rikuo was a child and used to play a lot together.
After the Gagoze incident, Tsurara was designated as Rikuo's bodygard along with Ao, fact that he never realized until she and Ao explained him themselves. At first he wasn't agree with the idea of Tsurara being around him all the time, but he slowly got used to it and enjoyed her company.
As any youkai, she likes to do jokes, but Rikuo is totally against of it, even if it's not dangerous, so normally she don't do anything. She just put his friends to sleep once so they can fullfil ther mission, but he didn't ay anything at all.
Rikuo doesn't seem to be bothered about Tsurara being the one who mostly of the time take care of him. He even likes her food, but the only problem it that it is always frozen.
Through the time Tsurara developed a huge crush on him, which made her act a little bit strange sometimes because of her nervousness or getting jealous when Kana was present. Naturally Rikuo is oblivious about her feellings and he just think that she's overreacting. At some point of the manga, and some omakes, it is hinted that Rikuo began to see her more than a friend and a subordinate, like if he got a crush on her too.
Rikuo unconsciously begins to be more protective with Tsurara, in both his Day and Night form, like when she was returning to the Main House alone in a snowy night and he went to pick her up, saying "How dangerous, walking the streets all alone at night" and "You'll get wet" (An ironic thing because she's an ice woman), and then walk her back home under an umbrella. Or asking her to not protect him anymore so she can be safe and not get hurt because of him, like in the battle against Tsuchi-gumo.
It seems that she became a very important person for him because when he saw how she got hurt by protecting him from the yokai otakus in the Hyakku Monogatari Clan Arc, he got furious and began to confront them all with Tsurara in his arms, not caring about being in his human form.
His trust in Tsurara is blindly, getting to the point of asking her most of the time to do Matoi with him before asking it to other yokai; or even asking her to take care of his mother and make the Main House a warm place where they can return to. In Volumen 25, in the Tankouboun edition, some time later, after all finally finish, Rikuo and Tsurara's relationship seems to be the same as always, but that changed a bit when they got trapped in the warehouse of the gym in school and almost share a kiss because of Rikuo's initiative before Aotabou arrives and interrupt them.
She and Wakana seem to share a rather close relationship. Tsurara often helps Wakana in the kitchen in making food (However, the food she makes is frozen though tasty).
Tsurara and Kana seem to share a minor rivalry. As Rikuo's bodyguard in the disguise of Tsurara Oikawa, she still maintains her close relationship with Rikuo. This often confuses and concerns Kana who assumes that they are dating. Kana also has been seen to be envious at the ease at which "Tsurara" and Rikuo became close so quickly. On the other hand, after Kana fell for Rikuo's Night form, Tsurara showed minor jealousy at it. However she protects Kana as her death would sadden Rikuo.
After the battle against the Hyaku Monogatari Clan, they share a laugh which can imply that they are beginning to accept each other.
- (To Rikuo) "I'll protect you... for all eternity. Because you are the one I exchanged sakazuki with."
- (About Rikuo) "He has many enemies, but he always carves his own path with unwavering conviction. And that is why I can always trust in him."
- The reason Tsurara wears a scarf is to keep inside the cold air she lets out from her own breath.
- She ranked 3rd in the 1st character popularity poll with 1202 votes. She ranked 2nd in the 2nd character popularity poll with 2165 votes. She ranked 2nd again in the third popularity poll with 2,636 votes.
- Tsurara means "Icicle" in Japanese.