Kuroka is a major character and main heroine in the story, A Tale of Three Dragons. Born as a Nekoshou, a sub-species of Nekomata, Kuroka is the older sister of Koneko Toujou. Having lost their parents, the two were taken in by a Devil who cared for them, but for reasons unknown, Kuroka killed him after awakening to her abilities. Since then, she has been on the run, labeled an SS-Class Stray Devil, and is to be executed on sight. Several years prior to the beginning of the story, while assuming the form of a black cat, she was found by Reishou Suzuya, who took her in and looked after her.