I Chose to Be a Fake Extra

A child shows up claiming to be Duke Maynard’s long-lost daughter, but he’s skeptical. However, Lilian came with proof, her best friend Swan’s locket, stolen from the orphanage’s headmaster’s office. After Swan died from an illness, Lilian heard the headmaster talking about Swan’s origins and his ruined plans to use her to gain the duke’s favor. She decides to stop living as an extra and live the life Swan was supposed to have.

Source: Tapas Includes 5 extra chapters.