Chamajuseyo, Daegong

Her life is nothing but lies.
Camellia was just 12 when she was taken away from her mother in the slums and forced to live as the son of an aristocratic family. But under the layer of secrets and lies, she never forgets. She continues to struggle to be her true self again, to reclaim the life of Camellia.
(Source: Manta)
Note: Chapter count includes a prologue, 3 spin-off, 2 specials and 13 side stories.