Complex social dynamics occur when complaints are voiced on firms’ social media channels. In combination, a complainer criticizes a firm, which may be responded to uncivilly by different online personas, i.e., Internet trolls or loyal customers, with virtually-present observers watching how a firm responds. This research examines customer-to-customer (C2C) uncivil commentary from troll persona and loyal customer persona comments perceived by observers to elicit schadenfreude: malicious joy due to another’s adverse event. Three studies show how C2C schadenfreude targeting a complainer elicits sympathy from observers, which influences observers’ future purchase intent. A preliminary study’s online content analysis using field data shows the frequency of C2C schadenfreude during social media service recovery. Study 2 uncovers moderated mediation of C2C schadenfreude-sympathy-purchase intent, with loyal customer persona comments producing more observer sympathy than troll persona comments. Study 3 finds the harmful effect of observer sympathy on purchase intent varies based on how or if a firm addresses the C2C dialogue. Taken altogether, this research uses a novel cognition (perceived schadenfreude from another’s comment), lesser-studied emotion in marketing (sympathy), and is the first marketing-related work to incorporate backlash theory from organizational management to exemplify how loyal customer comments produce a backlash effect in observers.