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 noble vampires have. She posesses the beauty of the typical Noble Vampires.

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 shown 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 comprised of the Kain, Aido, Souen, Toya, and other clans. Not much is known about her parentage, but her father or mother are 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 was 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 those girls who try to get close to him, especially Yuki 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 that Shiki may not really be himself as she notices his left eye is a different colour. She overhears Kaname telling Aido and Kain that Yuki 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. Later, 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.

Along with Akatsuki, Ruka follows Kaname in his new mission, though its not clear if she is happy with their new course as she has some gloom about her nature, but she appears determined not to leave Kaname's side. Kaname told Akatsuki when the time came, he would force Ruka to leave.

Kaname Kuran
Ruka has had an unrequited love for Kaname since she was a child, having a crush on him even before she met him and remains one of his most loyal followers. Kaname remains aware of her love and in return respects her. She decided to set aside her feelings for him after she learned of Yuki's true identity.

Akatsuki Kain
Kain is Ruka's cousin and they have been playmates since they were small, however Ruka is unaware of Kain's unrequited love for her.

Hanabusa Aidou
Hanabusa is also Ruka's cousin and has known her since they were young. Ruka is constantly seen getting into fights with Hanabusa.

Powers
Ruka's power is stated to be manipulation through illusions, but has not been demonstrated within the manga. She is also apparently able to control Level E vampires into making them destroy each other, as demonstrated in the anime.