Where does the Nun fit in?

For a detailed look at each of these characters, simply follow the link provided below to access Gradesaver's summary of the Prologue. In this summary, you will find the order (from highest to lowest) or status of each of the pilgrims. I assume that this is what your question refers to as far as "fitting in." Chaucer's pilgrims represent the different rungs of English society. The summary will supply you with this information in order of importance.