At the end of the story, Bobinôt and Clarisse bask in their respective spouse’s newfound joy, not realizing that it is the result of an extramarital affair. This is an example of dramatic irony because Calixta, Alcée, and readers all know the truth, while Bobinôt and Clarisse do not.
The irony comes across in moments like the following, when Bobinôt returns home after the storm has died down, afraid that Calixta will criticize him for being out with their son Bibi in the storm:
Prepared for the worst—the meeting with an over-scrupulous housewife, they entered cautiously at the back door.
[…]
Calixta was preparing supper. She had set the table and was dripping coffee at the hearth. She sprang up as they came in […]. She had clasped Bibi and was kissing him effusively. Bobinôt’s explanations and apologies which he had been composing all along the way, died on his lips as Calixta felt him to see if he were dry, and seemed to express nothing but satisfaction at their safe return.
Bobinôt moves from “prepar[ing] for the worst” when greeting his “over-scrupulous housewife” to having all of his apologies “die on his lips” as he realizes, with surprise, that Calixta is simply happy that he and Bibi made it home safely. While Bobinôt does not understand the reason for this change in his wife’s temperament, readers know that it is because she has just finished having passionate sex with her ex-lover Alcée and feels rejuvenated by it.
The way in which Calixta and Alcée take the liberating and loving energy of their sexual experience and channel it into their marriages highlights Chopin’s underlying message in the story—that infidelity is not inherently harmful but can, in fact, lead to more love and joy in the world. As she writes in the final line of the story, “Every one was happy.”