Emilia, noting that women are often scared of werewolves, plans to tell a tale with a good prayer to exorcise them. In Florence, successful merchant and devout Christian Gianni Lotteringhi lives with his wife, Monna Tessa. Quick, intelligent Monna Tessa (daughter of Mannuccio dalla Cuculia) takes Federigo di Neri Pegolotti as her lover.
The premise of Emilia’s tale raises assumptions about female vulnerability and fearfulness in order to subvert them. Monna Tessa’s family name, Cuculia, means “cuckoo” and its sound recalls “cuckold” (the word for a husband whose wife cheated on him). It later becomes clear that the meaning of “werewolf” in this context is less like the specific, modern idea of a wolf-man hybrid and more like a generalized “bogeyman.”
In the summer, Monna Tessa stays at her husband’s country villa which Gianni Lotteringhi visits only occasionally. She lets Federigo di Neri Pegolotti know when it’s safe to visit by turning a donkey skull that’s mounted on a stake in the vineyard: toward Florence for come, toward Fiesole for stay away. When Federigo comes to the villa after dark, he knocks three times to be let in.
The donkey-skull sign is both a demonstration of Monna Tessa’s cleverness—which will be important later in the story—and part of The Decameron’s commitment to specific descriptions, even in stories with crazy premises; Giovanni Boccaccio describes the mechanism in loving detail.
One day when Federigo di Neri Pegolotti is due to visit and Monna Tessa has prepared a nice meal, Gianni Lotteringhi turns up unexpectedly. She has a maid leave the meal in the garden but forgets to leave an explanation for Federigo, so he comes to the door. The knocking wakes Gianni, and Monna Tessa says it’s a werewolf that terrifies her every night.
After her husband ruins her plans, Monna Tessa tries to divert Federigo to the garden—less pleasant than sharing her bed, perhaps, but a place of safety and diversion where he can at least enjoy the good meal she prepared for him. Yet, her plan is undermined by simple human forgetfulness.
Gianni Lotteringhi assures Monna Tessa that he’s already said some efficacious prayers for safety. Inspired, she explains that an anchoress recently taught her a prayer to exorcise werewolves and she’s feeling brave enough to try it with Gianni there. At the door, she loudly recites a prayer telling the “werewolf” with its erect tail that it should leave her and her husband alone but could find food in the garden. Federigo di Neri Pegolotti understands, and he and Monna Tessa laugh about their close call later.
Gianni, since he is a pious and faithful man, doesn’t fear anything that comes in the night, but Monna Tessa must still come up with a way to secretly communicate with her lover and warn him off. Her clever plan hinges on having received secret religious knowledge from an anchoress (holy women who lived out their lives enclosed in small rooms attached to churches). Her prayer includes enough detail (such as the erect tail and her husband’s presence) to be unmistakable to her lover, and thus she successfully tricks her husband without getting caught.
Emilia notes that some people say that Monna Tessa had set the skull for “stay away” but a farmhand unknowingly spun it around; in this version Federigo di Neri Pegolotti lost his lady’s bed and didn’t get supper. An old neighbor of Emilia says both versions are true, but one refers to a different Gianni. She leaves it to her audience to pick their favorite version.
But, in another nod to realism that makes it feel like this story is based on true events, Emilia offers an alternative ending of the kind that arises when a true story has passed through enough tellers to have gained legendary status.