The whole building, architecturally, seems sort of torn between modernity and a very Old Money feel- Portions are smooth, white, and chrome, while others have landscape paintings with artful filigree and oak inlay.
The library leans fairly hard into the 'old money' side of things. The floor is patterned wood, the chairs are plush, there are chandeliers and latin mottos. It's not a vast museum-like library, much closer to a small local one, but definitely fancy.
"Welcome to my domain," says a woman in obvious raiment, positively nailing the 'librarian' look, with a pretty Asian face, blue hair in a neat bun, a purple/white vest sort of garment with shining buttons and stripes, elaborately patterned silk cape glittering with silver, shaded glasses, black gloves that flare into a star pattern at the wrist, and probably more behind the desk. "Miss Riley, is this Luna, Maeve's five o'clock?"
"Indeed. She wants to browse while she waits. Luna, this is Madam Pen, who prefers to be called that or 'the librarian'. Madam, Luna, a newly mantled spirit bearer - or perhaps spirit guardian?"
"Very good. You won't be able to check anything out today, and please don't try to re-shelve things yourself. We only keep books relevant to the life of a spirit bearer here, though that is a bit broader in some ways than some imagine when they hear it. May I help you find anything?"