Pandora's Secret (MIUCHI Suzue)

(from ebookjapan):

Aimée, a young girl living on the island of Pandora, was told by her mother from a young age not to take off the ribbon around her neck in public, and was separated from her mother when she was four years old.

But....

The story of Aimée's turbulent destiny, which is related to the secret hidden in the ribbon, begins.