Vivia Nihar is the heir to the Nubrevnan throne and the older sister of Merik Nihar. She has been appointed the temporary queen of Nubrevna.
Sometime after the death of her mother, Queen Jana, Vivia was bypassed for the Nubrevnan throne by her father, Serafin, despite it being Vivia's birthright.
Vivia appears only briefly in Truthwitch as the Captain of the Foxes, a group of Nubrevanan pirates.
Vivia is seen to actually be a good person who cares for her country. The "bad" decisions that she and Merik argued about in the first book were actually attempts by her to sidestep the Council and help the poor Nubrevnans. The Council was purposely blocking her and her claim to the throne, led by Serrit Lindsay, in an effort to enrich themselves, since the current king, Serafin, was slowly going senile. She is seen as a strong and competent ruler. Her one ally in the Council is seen to be Lord Sotar, Stacia's (Stix's) father, thus setting up a positive ground for Vivia's and Stix's relationship (see below)
Vivia and Merik have an antagonistic relationship due to their differing stances as leaders in Nubrevna. Despite this, Vivia cares for her younger brother.
Stix is Vivia's First Mate and closest confidant. In Windwitch, Vivia's deeper feelings for Stix are hinted at.