Read Hiznak's secret journal.

The capital was ruined by the rebellion of Sephir,
who burst the seed of contaminated Turasil in the city.
All the research records that we worked on for a long time
to save our sisters were destroyed.
However, we all knew from the beginning
that those who are completely fallen cannot be saved...
But at all costs of any side effects, we should stop the process
of addiction for sisters who have not yet become completely fallen.
That's why we did all we could to aid Dawn's escape,
for there is no light to help us if she dies.
...According to this secret note of the Thornwood Watch,
It says they helped the escape of Dawn, that is believed to be Brolina,
not that she ran away on her own...
Of course, we cannot fully trust this record just yet.
It may be important to know whether her escape from O'dyllita, or her
experiments to make the corruption fade was voluntary or compulsory,
but we'd never know what the truth is for now.
I believe it is only Brolina, who knows the truth.
But most of the Ahib who are not close to the Queen,
say that her life as a hostage was pathetic...
Though I don't know whom to believe,
I hope these records will help you at least a little bit.
I've got to go. If I leave my post for too long, they might suspect me.
No matter how friendly the Ahib may be, never let down your guard.