This is a wonderful parody of a medieval romance. Everything is reversed, the heroine isn't a beautiful Christian held by Saracens, she's a Saracen held by Christians. And Aucassin isn't a valiant knight, he shirks from his knightly duties to find his love... In one passage, he explains why he would prefer hell to heaven. And in the land of the Torelore, the king is in bed waiting to give birth. Though it's never cited as such, this is probably the earliest of the post-classical picaresque works of literature. 
 Be sure to read Lang's introduction.