Nightingale in her Mist was observing the change in the witches' magic power.
There were few chances to see such bright and colorful scene in the black-white world. Compared to the time when they were looking for Holy Mountain, their magic powers had increased a lot through daily practice. They could now control their power more accurately. But what was the most comforting thing for Nightingale was the expressions of her friends.
Despite Wendy's gentle inspiration and Cara's firm action, they were never able to sleep peacefully, even for one night, in the Witch Cooperation Association. Any little signs of arrest from the church and suspicion of the public could make them wake from their stressful sleep. Even when they were looking for Holy Mountain, they were not able to relieve their stress. No one knew Holy Mountain would really be a safe shelter for them. Back then, the witches were usually downcast with numb, vacant expressions.