Then, she remembered her goal and why she infiltrated this place. To seek vengeance but with her current strength, it was not enough to destroy this entire HQ.
With Narukami and Ryu fighting without holding back. Their very strength could very well destroy the HQ to debris.
She didn't have to worry about not fulfilling her goal and so, she basically had nothing to do.
She could only wait until this place crumbled yet she wasn't the type to lay wait while others were occupied. She would feel restless.
Therefore, she wanted to give it a try to venture deep into this passageway. Narukami and Ryu take it as important so probably this place was quite important for Fallen Nightless.
The risk was unknown but that wasn't a reason for her to quit. She simply had to proceed carefully.
While Narukami was responsible for destroying the place, she at least could complete what Narukami originally wanted to complete.
