Rukia is a Soul Reaper in the 13th Division under Jūshirō Ukitake. Shortly after meeting the main protagonist of the series, Ichigo Kurosaki, who can see supernatural beings such as Soul Reapers, she is forced to give him her powers in order to fulfill her duties as a Soul Reaper
Rukia Kuchiki is a Shinigami who was sent on a Hollow extermination patrol in Ichigo's home town. Though her physical appearance is that of a teenage girl, in reality she is over 150 years old. Rukia is forced to transfer her power to Ichigo and assume a temporary lifestyle as a regular Human. She registers at the local high school and takes up residence in Ichigo's closet, while teaching him how to be a substitute Shinigami in her place.