Sienna (シエナ, Shiena) is a character in the special pilot chapter A Mother's Determination. Born and raised on an unknown plantation at Grace Field House, Sienna now works as a sister at Grace Field Headquarters.
She seems to have curly orange hair and light eyes. She wore the standard orphanage uniform made for the plantations' Sisters, which consists of a black dress with a white blouse underneath it and a white apron over it
Sienna's only desire was "not wanting to die" being a girl without any strong demand she has proven herself to be quite useful towards the demons, she is also shown to be fearful
Like all the sister she is shown to be resentful towards her, but respects her, she also thought that Isabella was amazing ever since she was a girl and that she was scared of her because of the latter's performance; perfecting the physical and written tests, nonetheless she stood up with her saying they never had a Grandma like this and is shown to be grateful towards her.