Athanasia de Alger Obelia

Athanasia de Alger Obelia is the main protagonist of the manhwa "Who Made Me a Princess" as well as the first princess and only heir to the Obelian Empire. After reading a book named "The Lovely Princess" on a shunned princess named Athanasia, the protagonist falls asleep with sleeping pills and finds herself in the infant body of Athanasia from the book.

Athanasia, also known as "Athy", is the daughter of the emperor Claude de Alger Obelia and Diana, a dancer he deflowered after meeting at a royal banquet. Claude's harem previously occupied the Ruby Palace, however, he massacred them when Diana died giving birth to Athy.

Athy makes her goal in her new life to avoid the execution of the previous Athanasia on her 18th birthday.

(Source: Who Made Me Princess Wikia)