The Sorceress (Ludmila)
The woman who walked into Burgomaster Krezkov's house in session 29, summoned a beholder when the party stood in her way, and left with Myra and Kyra. The sisters went willingly.
She did not come alone. Her people waited outside the house and never came in.
She calls herself Ludmila. It is not the name she was born with.
In session 30 the party followed Myra to her den. She drew blood from Myra and Kyra with a blood transfer spell and said plainly that she and her people want to understand the curses. When Logi cast fire inside, she knew it for Strahd's, was furious that he had brought the lord into their home, and caged him. She caged Mark for the evil sword he carried. Myra pressed her to take Kept Memories out of Strahd's castle, to bring Taara over to their side. Then Taara, Myra and Logi left through Taara's Amulet of the Planes, taking a few spokes of the cage with them, and the Sorceress was left with Kyra, both sisters' blood, Khione and Yager, Mark (a pure soul now, behind broken bars), and other werewolves closing on a den that Logi's fire had given away.