The initial description of the library had me thinking of 'the Man Who Was Thursday', a book which includes its own absurd secret society. Also, anyone interes

The initial description of the library had me thinking of 'the Man Who Was Thursday', a book which includes its own absurd secret society. Also, anyone interested in real-world social games might enjoy Journey to the End of the Night (http://ichaseyou.com/ http://ichaseyou.com/). It's not a secret society, but it shares some elements of roaming through your city, playing a game with strangers, and creating your own adventures.