Diana Black is a recurring character in the Jewelpet anime series. She is a sophisticated and mysterious black cat Jewelpet, known for her elegance and cunning personality. Diana often acts as an antagonist, causing trouble for Ruby and her friends with her clever schemes. Despite her mischievous nature, she has a complex side and occasionally shows a softer heart. Diana plays a significant role in the series, challenging the protagonists and adding depth to the show's narrative.