Shishi To Cinderella summary:

Yvain has been working as a maid in the Sandell household since she was 15. One day she accompanies her employers on a luxury cruise ship. Who would have thought the ship would sink! Yvain is swept away by the strong currents of the sea... When she awakens, she finds herself on the Island of Lions, where the mysterious yet alluring marquess, Juan, lives...