Siana is a member of the Night Clan. Later chapters in the story hint on Siana being the child of Nex and Serin, along with being the sister of Xix. She is Xix's childhood friend that was accidently murdered by him.
She is a petite, thin female that is somewhere in her mid-to late teens.She shares many similarities with Serin. She has pixie-cut purple hair, and green eyes that are a similar shade to Serin's. Siana is often seen sporting a grin similar to the Cheshire cat. She wears a bikini top covered slightly by a hoodie that hangs off her upper arms with a design on the inside, short shorts, and ripped up knee-highs with leather boots. She has a scar along her heart area. It is noted as a child Siana's hair was white and she wore white clothes which contrast to her dark clothes as a teenager.
Siana has a personality that can be contrasted between light and dark. She shows compassion towards those who suffer, but usually after she is done with taunting them. She is not completely stable mentally. She is amused by Ninurrta's failed attempts on killing her since she notes he lacks a murderous intent; then becomes excited from Ninurrta's ice attack freezing the enemy solid down to their blood. She picks on him about Nex's demand to bring Ninurrta back dead or alive; but when he finally breaks down she comforts him. As a child she tried to keep her sadistic side hidden from Xix; and was burdened by other village children bullying her. Siana has a care-free attitude and chooses to not take things too seriously.
Siana is shown in Xix's flashbacks with her face hidden. The last memories Xix has of Siana is her dying.
Later on, she makes an appearance to a runaway Ninurrta at the Regis's seal removal ceremony-which will reveal who is his true son. She kidnaps Ninurrta and manages to convince him to join the Clan of the Night after Ninurrta learns the Regis doesn't care if he dies.(During the flee from the palace, Xix does see Siana taking off on an air dragon). Ninurrta does not completely trust Siana, but lacks a place to return. They travel to the Night Clan's territory where Siana reveals to be working under Caladborg.