Sunny Snow Flurries

The servant girl, Gae-Ji, is forced to marry Yeon-Su, the son of a grand prince who has been arrested for treason, in place of the young lady she used to serve. However, the rebellion is successful and Yeon-Su becomes the crown prince, while Gae-Ji suddenly becomes the crown princess...

Will she be able to play the role of the fake crown princess safely?

(Source: Lezhin, translated)