During the quest https://en.uesp.net/wiki/Tamriel_Rebuilt:On_Daedric_Design, you're directed to the bookseller Uleni Tenandus through a topic of the same name.

However, the dialogue line is filtered to all NPCs in Necrom and there's no unique line for Uleni, so she speaks of herself in the third person and directs you to her shop in which you're currently in.