Sei Rhuka

Sei is a character in "The Crown and the Flame". She's got her first appearance in book 1, chapter 11.

Anu Rukha
Anu is Sei's grandfather. He affectionately calls her "little Sei-Sei". Even though Sei has got problems to show it, it's clear that her grandfather is very important to her, she even wanted to kill herself when she thought, Anu got in Hex's claws.