The Chevalier de Mirvel is the brother of Madame de Saint-Ange and one of Dolmance's lovers. He regularly has sex with his own sister, and it is Chevalier who convinces Dolmance to make an exception to his renunciation of women and come to Madame de Saint-Ange's boudoir. He is renowned for his unusually large penis.
The Chevalier enters into Eugenie's education midway through the process. Dolmance determines that the Chevalier's member is perfect for the breaking of Eugenie's hymen. Later, he uses his lilting speaking voice to give an extended reading of the pamphlet "Frenchmen, Some More Effort if You Wish to Become Republicans."