Olimpia Kutuzova and Carlo Cafiero had a romantic relationship. They met in 1873 when Cafiero was in Russia, and their relationship began as they both shared a common interest in revolutionary activities. Cafiero was an Italian revolutionary and a mutual friend of Mikhail Bakunin, while Kutuzova was a Russian revolutionary. Their relationship was not only personal but also political, as they both were involved in the revolutionary movement against the Tsarist regime. Cafiero even traveled to Russia in April 1874, possibly to be with Kutuzova, indicating the depth of their connection. This relationship is documented in various historical sources, including Wikipedia's page on Carlo Cafiero.