Marion Benigni is a young girl who lives and grows up around the Kaleido Stage, the world-famous circus where her father, Jean Benigni, works as a set designer. Her mother, Cynthia, was a former trampoline star at the same stage, but she died in a tragic accident during a performance. This loss deeply affected Marion, making her initially withdrawn and obstinate. However, she gradually opens up to Sora Naegino, the main protagonist, who becomes one of her closest friends. Marion is the youngest member of the main cast, even younger than Rosetta Passel, and she is often seen as the honorary little sister of the Kaleido Stage performers.

Her primary motivation stems from a need for connection and safety after her mother’s death. She finds comfort in caring for Jonathan, a seal that lives at the stage, and she appears to have an unusual ability to understand Jonathan’s behavior and communicate with him. In the story, Marion serves as a supportive friend and a reminder of the family-like bonds that form within the Kaleido Stage community. Her role in the OVA Kaleido Star: New Wings Extra Stage is minor but meaningful; she is part of the ensemble that helps Rosetta during the rehearsals for The Amazing Princess Without a Smile. Her relationship with Sora is especially significant, as Sora’s warmth and persistence help Marion overcome her grief and become more open and trusting. While she does not perform on stage herself, she is often seen helping behind the scenes and contributes to the cheerful atmosphere of the stage. Her development centers on learning to trust again and embracing the family she has found among the performers and staff.