Who is Ghosts from Heir Apparent and what is their importance?

There are approximately a hundred restless spirits, who follow Janine home from the catacombs when she goes to retrieve the money taken by Rawdon. The ghosts crowd the drawbridge, making it hard to bring up the money, and the cluster in doorways making it impossible to open or close them at times; and making all manner of noise at night from shrieking to rattling chain.