When Sianna was alive, she was described by many of how beautiful she was, in her Shinigami form Sianna tok the form of a naga. Her tail is decorated with brown and gold coloured, pepple scales, a grey underbelly. What is notable about her appearance was her locks of tendrils of living snakes, she can turn them back into her original hair anytime she wishes. Her breasts are easily noticed but only covered over the nipples by two of her hair tendrils. She has a curvacious figure and wide hips. Her skin is soft and creamy colour, golden eyes and slit pupils.
Sianna is very kindhearted but in battle she would become cold to her opponents to protect those she loves. She is bright and acts as a freespirit after she died, as to why she felt free without clothing and loved to see new things.
When R'yac lost his parents as a child she was mostly protective of him, she acted like an older sister to him after the first years since they first met on his homeworld but as he grew older she developed feelings for him. Despite being a spirit she sometimes forgets that she can phase through objects.