Ruka Souen

Ruka Souen (早園瑠佳, Sōen Ruka) is a Night Class student popular among the Day Class boys and one of the most faithful and protective of Kaname Kuran's followers.

Name
Her given name is composed of ru meaning lapis lazuli and ka meaning good-looking or beautiful. Her surname is composed of sou meaning early or the obscure meaning of strong fragrance and en meaning garden. The alternative spelling of Ruka's name is Luca, as published by the official Vampire Knight fanbook Japanese release.

Appearance
Ruka has pale brown hair that falls in waves down to her waist. Her eyes are a few shades darker than her hair, and she has the same pale, creamy skin tone that all vampires have. She possesses the beauty of a typical Noble Vampire.

Personality
Ruka usually reflects a haughty, bored and uninterested person to the rest of the world, probably due to her noble upbringing. One of her defining characteristics is her love for Kaname Kuran. Since they were children, Ruka has been tied by loyalty and admiration for him, angry at all those who disrespect him and disdainful of all girls who fawn on him. Her possessiveness made her hot-tempered and jealous, but her love for Kaname also brought out a vulnerable, self-doubting aspect of her usually proud personality, which she only expressed to her close friend Akatsuki Kain. She realized how overjealous and how she was only thinking of her own feelings and matured. Since giving up on him, she has shown a gentler side to her personality. She even gave Yuki, whom she was jealous of before, etiquette lessons and during the ball, told her that she was glad Yuki and Kaname were getting along so well.

Although Kain has been in love with her since they were children, she appears to be oblivious to his feelings for her. She is elegant, and very ladylike.

Background
Ruka grew up privileged, as the daughter of a noble family. Her family is part of what is referred to by Asato Ichijo as the "Aido faction", which is comprises of the Kain, Aido, Souen, Toya, and other clans. Not much is known about her parentage, but her father or mother is possibly part of the Senate or in another high position, as Ichijo refers to her as "The daughter of Souen". Ruka came to Cross Academy to be closer to her long-time idol, Kaname Kuran, with whom she is in love. On their first night at the school, she asked Kaname to drink her blood to prevent him from drinking Yuki's blood which he accepted. He has refused it since, which deeply hurts her, even though she has always expected such.

She is roommates with Rima Toya. The Souen family are pro-monarchy like the Aido, Kain, and Toya families.

Plot Summary
At the beginning of the story, she is very loyal to and defends Kaname and despises all girls who try to get close to him, especially Yuuki to whom Kaname gives special attention to. She tries to ask Kaname to drink her blood after their encounter with Asato Ichijou but Kaname refuses, causing Ruka to be rather sad (although she knew he was going to refuse anyway) as he had drunk her blood on a previous occasion when they first stayed at Cross Academy.

She becomes upset with the fact that Kaname chose Yuki to be his lover and locks herself all day in her room. The possessed Shiki attempted to toy with her but was halted by Kain and afterwards, Ichijou. She is seen noting could Shiki really be himself as she notices his left eye is a different colour. She overhears Kaname telling Aido and Kain that Yuuki is his sister and wife-to-be and finally accepts Yuki being Kaname's lover. She even gives Aido shoes to give to Yuki to wear. She seems much more mature and level-headed now, recognizing the foolishness of her obsessive feelings for Kaname, though she still shows just as much dedication to him as before but with a new calmness. When Rido Kuran's servants invaded Cross Academy and attempted to attack the Day Class students and present them as gifts to their Master, Ruka alongside Kain, worked to defend the Day Class girls. Following the breakup of the Night Class, she, Aido, and Kain returned home to see their families for a little while, because they did not know where he had disappeared to and decided that they would search for Kaname and Yuki after their short visit.

Following the one year timeskip, Ruka has been aiding Aido in training Yuki in order to turn her into a lady. Kaname sent Ruka and Kain to monitor the Hanadagi estate for any signs of movement, upon returning to update Kaname, Ruka troubled by their upcoming plan, gives Yuki a cold response, who concerned by the out of character response, asks Kaname if he has done something to Ruka. Ruka later takes care of Kaname after his hand is damaged by wielding the anti-vampire sword.

Kaname Kuran
Ruka has been an admirer of Kaname's since before she even met him and remains one of his most loyal followers. She asked Kaname on many occasions to drink her blood, to which he refuses, much to her sadness. Upon discovering Yuki is his pureblood sister and fiance, she gives up trying to pursue him and keeps her unrequited feelings to herself. She teaches Yuki how to be more ladylike after the one year time skip.

Akatsuki Kain
Kain is Ruka's best friend and they have been playmates since they were small, however Ruka has never been made aware of Kain's feelings for her. They are however, presumably close as Ruka is evidently vulnerable whenever she is around Kain (such as the situation where she fell into Kain's arms and cried out her sorrows of her feelings for Kaname after he refused to drink her blood) and she is seen smiling and saying "Thank you," to Kain after he protected her from a possessed Shiki.

Powers
In the anime, she possesses the ability of mind control. In the manga, her powers have not been shown yet although offical fanbook stated that she can manipulate the enemy through illusions.