Kiyone Kotetsu is the co-3rd seat officer and acting lieutenant of the Thirteenth Division in the Gotei 13, serving under Captain Jūshirō Ukitake alongside her counterpart, Sentarō Kotsubaki.
Kiyone is the younger sister of Isane Kotetsu, who serves as the Lieutenant of the Fourth Division, responsible for medical and supply relief. Unlike her more reserved sister, Kiyone is energetic and enthusiastic, though she shares Isane's strong sense of loyalty.
Kiyone holds her captain, Jūshirō Ukitake, in high esteem and constantly seeks to impress him, sometimes at the expense of her partner, Sentarō Kotsubaki. She is also a member of the Shinigami Women's Association, like many other female Shinigami.
Her infatuation with Captain Ukitake often provides comic relief, especially when she engages in playful rivalry with Sentaro over who admires or loves him more, much to Ukitake's exasperation. In one omake chapter, she even assists Soifon in pinning Ukitake to a tree with kunai knives and taking "sexy" photos of him, all while nervously apologizing, "I'm sorry, I'm sorry!"
(Source: Bleach Wikia)
