Scholar who walks the night

Set in an alternate Joseon dynasty, Jo Yang-sun is the daughter of a nobleman whose family loses everything when her father is framed for treason. To make ends meet, Yang-sun begins cross-dressing as a male bookseller, and meets the handsome and mysterious scholar Kim Sung-yeol, who works at the Hongmungwan. Sung-yeol is a vampire, and he continues to be haunted by the long-ago death of his first love Lee Myung-hee, especially when he meets Myung-hee's present-day doppelgänger Choi Hye-ryung, an aloof nobleman's daughter. Meanwhile, the evil vampire Gwi resides in the royal palace and uses his powers and political machinations to prevent the Crown Prince from ascending the throne. [Source: https://en.wikipedia.org/wiki/Scholar_Who_Walks_the_Night] 

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