Im Ye Jin

Dan Bi is a high school senior who has given up on math. On the day she is about to take the KSAT for college, she is transported back into the past during a freak rain shower. She finds herself hundreds of years in the past at the height of the Joseon Kingdom, which is suffering from a severe drought. She encounters King Lee Do who yearns to learn advanced mathematics and falls in love with him. This is a romance that transcends space and time with two lovers who come to know each other on a deeper level. (Source: MBC)

Han Ji Eun, an aspiring scriptwriter, lives in a house called "Full House", built by her late father. One day, her two best friends trick her into believing she has won a free vacation and sell her house while she's away. On the plane, she meets famous actor Lee Yeong Jae. Through comedic events, they get acquainted during her vacation, and when she returns, she discovers her house has been sold to him. Though they don't get along with each other (because of her messy tendencies, his bad temper and zealous cleanliness), they agree to live with each other. In the beginning, Ji Eun works as his maid in order to buy her house back. They alter their arrangement when Yeong Jae decides to win back the love of his life, Kang Hye Won. In a bid to make Hye Won jealous, the two protagonists enter into a contract marriage with a six-month term. Complications arise when the couple starts to fall for each other. (Source: Wikipedia; Edited by: unninette at MyDramaList) ~~ Adapted from the manhwa “Full House” (풀하우스) by Won Su Yeon (원수연).

Wealthy plastic surgeon Kong Gi Tae is a successful and happy bachelor who does not want to find himself a wife. He believes that his life is perfectly planned, and being single is the only option he can accept. However, his family is badgering him to marry. In an effort to get his parents off his back about the constant string of blind dates and marriage prospects, Ki Tae purposely brings Ju Jang Mi home to meet his parents, posing as his girlfriend, certain that they'll never approve of her. (Source: WeTV)

Two wannabe spies break up when one of them gets fired. Years later, both end up being spies working for different units, so they have to keep their covers up in real life. Gil Ro uses his real identity, hence why he was seemingly fired, to spy on his rich father. So, when Kim Seo Won appears as a new employee, he wonders if she really is just a doppelganger of the woman he loved. (Source: MyDramaList)