-Styg

My suggestion is that if you can find a way to justify it to fit the story you're telling, generally the audience will be accepting of it. I've seen stories here on WL that when something dangerous entered the Library, it used some sort of magic barrier to prevent the Library from noticing it ( a-cold-moon-sets-on-the-shelves ), it was created from a discarded husk of insectoid staff ( the-bibliovores ), or they moved quickly enough to not get caught.

With the case of 106, I'd ask yourself 1, what does it want to accomplish in the Library, and 2, what do you want the end result of them being in the Library to be? I can easily see 106's abilities giving it a mobility advantage to outrun the staff, or to be deadly even to Library staff in a fight. But since both of those damage the Library, I would strongly suspect the staff would be hunting it down the entire time its there. That could lead to a cool chase or fight scene, but if you don't want that to be what happens, then I'd consider a stealth approach or something helping 106 get into the Library unnoticed.

-DrSoot