Even years after reading the story, the two characters that jump to mind are two of the religious ones: The Monk and the Prioress, Mdme. Eglentyne.
With Mdme. Eglentyne, even though she is a religious and supposed to be humble woman, she conducts herself as aristocratic, uses her French to impress, and her prim and proper mannerisms are a bit curious. She also comes across as over-dramatic and a bit of a fake.
In the case of the Monk, Chaucer asks an interesting question to explain why the Monk is rebellious to the rules of no-hunting. He asks "why should a monk go crazy with study and rules"- Meaning that maybe in his opinion, no monk follows the rules they preach, and they may not even be that smart.