Amber Bourgeois, formerly Cimarosa, is a foreign exchange student from Italy. At a boarding school, she met Chloé Bourgeois, her half-sister. After finding out about how Chloé wanted to change, she transfers to her school and lives with her at her father's hotel. She attracts a lot of attention, some good and some bad. When two heroes show up out of nowhere, she is, at first, skeptical about them. However, she unknowingly attracts some romantic attention from the local cat hero, Chat Noir. She feels bad about how he has to deal with a partner who treats him like a sidekick. Not only that, but a certain bluenette seems to have an unhealthy obsession with her sister's childhood friend. Amber takes it upon herself to expose both Ladybug and Marinette for the awful people that they are, not knowing that they both are one and the same.