Be Quick Or Be Bent
Kurayami is from the same ninja clan as Kagemaru, also the practitioner of the soft body ninjutsu, the type of martial arts similar to the soft bone kung fu, but more focused on hiding and more extreme flexibility.
Kurayami has the most unique body and moves with the grace of a young and lively black cat. Wearing her black bodysuit, she gives the impression of being made of a single piece of elastic rubber. She can stand and turn her feet around so much that the toes point completely backwards, and her feet themselves are so flexible that a foot's toes can touch its own heel. Similarly, her fingers can fold completely backwards and can be pressed against the outer side of the palm.
Her torso is extremely pliant, for several hours every morning she can be seen bearing an impossible steel cincher around her waist, while in the evening everybody gathers to watch a special massage that looks more like an extreme stunt not to be found anywhere else, in which a heavy man tramples the girl's elastic ribcage like a pillow, squishing it almost to the floor, as if the ribs were made of cartilage.
Despite all these amazing abilities, Kurayami is not allowed to go on real missions, as she is more like a mascot of the clan and everyone's example of how flexible the ninja's body can be. But Kurayami is not a toothless cat, she is well trained to handle her two short katanas in case of true emergency, though more regularly they're used to entertain the clan's leader and other members with some dancing and acrobatics.