Shakugan no Shana Vol 5 pg 24

From this point on was a winding corridor leading to the innermost depths of the ‘Tendōkyū’.
Inside, that skeleton clad in rags—Shiro, as the girl called him—was waiting. As an
assailant, of course.
In fact, it was rare for him to attack her outside this corridor. There had been countless days
when she had not been attacked at all. Today’s attack outside was part of her training, to
teach her to maintain constant vigilance.
But inside here, it was different.
In this corridor, which the girl had to pass through every day—when she left the innermost
area in the morning after waking, and when she returned to sleep at night, as she was
now—he would always attack, once. And it was not the half-hearted kind of attack she
experienced outside, meant to test her ability to be wary of a surprise attack and deal with it.
The danger level rose to the point of being crushed to a pulp.
The girl had already experienced, countless times, losing consciousness inside and being
nursed by Wilhelmina, or suffering serious injuries and enduring the pain for weeks.
Despite that, she passed through here twice a day. Like her other training, it was not forced
upon her, nor was she sure when she had started doing it; it was, for her, just part of her
daily life.
She knew that whether she was attacked there or fought it off depended on her own
strength.
In this ‘Tendōkyū’, in the world as she knew it, there was no one to help her.
If she denied what was and threw a tantrum, there was no one to answer.