Catherine Breillat’s film is an adaptation of Jules Barbey d’Aurevilly’s 19th-century novel and perhaps her first that doesn’t transform sex and cinema into punishment. Maybe the period setting makes the difference, or the unwitting comedy of casting the buffoonish Asia Argento as La Vellini, a notorious courtesan in post-Napoleonic France. Adorned with gaudy mantillas and piled-up coiffures and puffing on a cigar, she’s kind of a cross between Goya’s Naked Maja and Carmen Miranda. No wonder jaded nobleman Ryno (petal-lipped boy toy Fu’ad Ait Aattou) can’t resist, not even when their liaison threatens his marriage with the icy, rich Hermangarde (Roxane Mesquida). Une vieille maîtresse is like Jacques Rivette’s Ne touchez pas la hache|The Duchess of Langeais remade as softcore S&M porn. “Good old Vellini,†Ryno chuckles as she slashes his face and licks his blood off the blade. Good old Breillat. French | 114 minutes | Kendall Square