All About: Rukia Kuchiki was from an orphanage, she had amazing spiritual powers and alongside with her, Renji too had amazing spiritual powers. After they growed up, 3 of their famaly members died, so, Rukia and Renji joined the Soul Academy. They soon found out that most of the students at the Soul Academy came from a noble family. After studying for quite a while, the Kuchiki family decided to adopt her, and asked her to make a conclusion. After consulting Renji, who thought she should join the Kuchiki family, she joined them. For after she joined them, she graduated immeadietly and joined one of the 11 squads. Rukia was borned on the 14th of January. Her height is 144 cm and her weight is 33KG. She likes bunnies and she dosen't like to wear tight clothes. Now: Rukia gave her powers as a soul reaper to Ichigo Kurosaki, for saving his family, thus commited a serious crime and was going to be exterminated. Until Ichigo Kurosaki rescued her from the Soul Society.
During the time, Rukia was switched to different cells, there, she rethinked her past, we get to know that she once admired someone called Kaien, from the Shiba family. Kaien's brother rescued her, not knowing that she was the shinigami that killed her brother, after meeting her, he was shocked. But he brought her out, when they ran out, Kuchiki Byakuya, Rukia's brother. He released immensely strong reaitsu, which drove Rukia to her knees because of the pressure. He severely injured Ganjyu, right when he wanted to kill Rukia, Captain Ukitake, the 13th squad captain appeared and convinced Byakuya to not kill Rukia, then head off with Byakuya, but not before Ichigo appeared.
Ichigo and Rukia had a little arguement, then he attacked Byakuya. To cut a long story short, he rescued Rukia after he acquaired Bankai. But then, Aizen took the Hougyoku from Rukia's body. After that, everything ended and Ichigo and his friends return to their world.
Now, the arrancar, something Aizen created from the Hougyoku, attacked the human world. Rukia returned and this time, she gained her powers back. Her zanpaktou's name is called Sode no Shiyaruki, the whitest sword in Soul Society. The battle with the arrancar continues currently.
Note: This is some thing bout RUkia, not a summary of the whole story.