"I can never forgive anyone who attempts to destroy what I must protect."

Rukia Kuchiki is the current captain of the 13th Division. She formerly served as lieutenant of the 13th Division under Captain Jūshirō Ukitake. Rukia is the adoptive sister of Byakuya Kuchiki, the younger sister of Hisana Kuchiki, a friend of Ichigo Kurosaki, the mother of Ichika Abarai, and is married to Renji Abarai.

Short and petite, Rukia has light skin and purple eyes. Her hair is black, reaching her shoulders, with several strands of hair always hanging between her eyes. Byakuya has stated she strongly resembles her sister, Hisana Kuchiki. As a Shinigami of the Gotei 13, Rukia wears a standard shihakushō. 17 months after Aizen's defeat, Rukia wears her hair cropped into a bob which hangs about her face. She wears a fingerless white tekkō, similar to Byakuya's, which extend above her elbows. As a lieutenant, she wears her Division Badge around her uniform's left sleeve, which has been shortened to just reach her upper arm.

Ten years after Yhwach's defeat, Rukia's hair is in a style similar to the time before Aizen's defeat, but much longer. She also now wears a typical captain haori over her usual Shinigami shihakushō.

Twelve years after Yhwach's defeat, Rukia wears her long hair in a sideways ponytail.

She likes to climb to high places. Rukia likes everything rabbit-themed, and becomes quite sensitive when someone insults her obsession with them. People often have difficulty understanding her drawings, which are typically rabbit-like, and doesn't like it when people complain about their quality. Rukia's favorite foods are cucumber, eggs, and rice dumplings.