Ruka has an average appearance for a teenage girl. She has wavy blue waist-length hair which is always tied up with her bangs parted in the center. Her eyes are a light pink colour.
In the school she went to when she lived with Richter Sakramaki, Ruka wore a white polo shirt with a black waist coat, red bow tie with a blazer, knee-length black stockings, a black skirt and black boots.
Now in the same same school as Yui, her school uniform consists of the black school blazer with a black deep V-neck vest over a white button-up dress shirt with frills near the neckline. She has a white bow showing through the V of the vest and wears a red bow tied to her neck above the white bow. The bottom is the black uniform skirt that stops above her knees with a white petticoat underneath. She wears it with black knee socks and black boots.
Her default outfit consists of a purple jumper with light pink at the collar and sleeves, along with black shorts and black boots.
Ruka is a kind but also a hot-headed girl. She treats people with kindness unless they do something that she doesn't like, for example flirting with or touching Yui. Ruka is not afraid to speak her mind and also not afraid to do anything to save her friends and family. Ruka is very strong willed which is what people admire about her, Ruka doesn't care about dying, she only cares about saving people who are precious to her.
Ruka is very flirty towards girl and is not afraid to tell them whats on her mind, however if she sees someone flirting with girls that they do not enjoy then she will step up.
Ruka lived with Yui and their adoptive father in a large house, she and Yui helped their father out t the church. Ruka was confused with herself by the time she was eleven, as she found herself feeling for girls as boy should do, when she found what a lesbian was she was happy and immediately told Yui who was happy that her sister found out why she was so confused with herself, Yui told Ruka that she will always be by her side and will continue to be her sister and love her.
However Ruka would not come out to her father Seji as she fears that he will abandon her and so never told him, despite encouragement from her friends, who she also told and were happy to accept her. Yui and their friends would be the only people to know about Ruka being a lesbian, and when girls got jealous of Ruka talking to boys they would joke about it when together.
Ruka would get close to a girl called Emiko, who also took an interested Ruka, Yui and her friends would tease about the two dating which Ruka would deny. The two girls started to see each alone and get closer and eventually kiss, making Ruka happy. However it would turn out that Emiko had no interest in Ruka and was simply using her to get another girl jealous, Ruka would be heartbroken by this and seeked her friends comfort. When they told Yui she marched off and they followed her, they saw her walk up to Emiko and slap her, greatly shocking. Yui told Emiko that she if she ever goes Ruka again she would get something more greater then a slap, Ruka felt touched that her sister would do something like this, Yui told her that no one messes with her sister.
Ruka got separated from Yui when their father moved to Europe for his work, Ruka was doing different studies then Yui so so Seiji sent her away from Yui, she ended up living with Richter Sakamaki. Richter was kind to Ruka when she arrived at his mansion but he soon changed and got possessive over her.One night Ruka tried to escape but Richter caught her and gave her punishment, which would happen if she did something wring or if he was angry at her.
Richter starts to go out more often and coming back at night drinking Ruka's blood which makes her tired when she's at school. One night Ruka wakes up to a sound of footsteps downstairs, she follows the which leads her to the kitchen to find Laito Sakamaki. Ruka quickly finds out that Laito is Richer's nephew and Laito is confused as to why she is living with his uncle. Richer appears and becomes angry at Laito, soon Laito leaves and Richter gives Ruka punishment.
A few days later Koneko is scared and worried because Richter has been gone for a few days and hasn't returned and Ruka walks in the back garden where she meets Laito again, they talk and she finds out that Yui is living with him and his other brothers, she also finds out that Yui is a vampire. Laito tells Ruka that Richter hasn't returned because he's dead which shocks Ruka but she is happy because she can finally escape. Laito then took her to the Sakamaki mansion where she is finally reunited with Yui.
Ruka truly loves Yui as a sister and always protects her danger. She stands by Yui's side no matter what and always gives Yui comfort. Many people describe them as 'lovers' on how they act with each other, Ruka said that if Yui wan't her sister then she would happily date and marry her, no one knows if this is a joke or the truth. Ruka and Yui have a very strong bond that they can easily tell if one of them is lying.
Ruka will put her life on the line to save Yui as Yui would do for Ruka. They are very comfortable with each other.
Seiji Komoricoming soon...
Ruka and Ayato didn't get along with each other at first because Ayato always tried to be perverted with Yui to which Ruka would interfere causing Ayato to be angry, however the two get better along the way, this is because they are both protective over Yui, they love revenge and pranks.
Laito was the first of his brothers to meet Koneko, after he killed Richter (or so he thought) he came to see Ruka and told her that he killed Richter, he also told her that Yui is a vampire and is living with him and his brothers, Laito then took Ruka to the Sakamaki mansion. .
Ruka and Shu get along very well, she gives him the nickname 'lazy ass' for his lazy personality. Despite Ruka being lazy herself she does get up and do work unlike Shu, Ruka tries to get him to work but fails which annoys her.
Reiji Sakamaki Edit
The two got rocky with first interactions which continued for a while and despite not liking Reiji's uptight attitude Ruka does respect some of his rules and asks, she does not enjoy being an experiment for him however as he used Yui.
Kanato Sakamaki Edit
Ruka and Kanato have a some what friendly relationship, with them both loving sweets and a fondness for stuffed animals. Ruka does get freaked out by his outburst and complains that he acts like a child.
Subaru Sakamaki Edit
Like most of the brothers Ruka and Subaru did not make good impressions upon first meeting, Ruka came to trust Subaru after Yui told her that Subaru gave her the chance to escape.
- Ruka is scared of spiders, sharks and gore, she dislikes blood and horror relating things.
- Ruka has a huge hate for KarlHeinz.
- If she had to choose Ruka would rather live with the Sakamaki's then the Mukami's and Tsukami's.