There are many main characters as it's a collection of stories. Some of the well - known ones are Lucifer, Adam, Hercules, Samson, etc. These characters come from different sources like the Bible, Greek mythology and other historical or legendary accounts.
In 'the monk's tale full story', the main characters are diverse. For example, Lucifer is a significant one. He was once an angel in heaven but his pride led to his fall. Adam, the first man in the Bible, also features. His disobedience to God led to the expulsion from Eden. Hercules from Greek mythology is there too. His strength was great but he was also subject to the whims of the gods and faced a tragic end. Samson, another strong figure, lost his power due to his love for Delilah.