Both feature a student/teacher romance between the older FL who tutors him and the younger ML who falls first. In both dramas, the ML has a strained relationship with his father, and his mother is no longer living.

Both are age gap romances with a young ML and an older FL, with the ML falling first. Both dramas have a similar tone and vibe.

Both are age-gap romances with an older FL and a younger ML who falls for her first.
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Both dramas feature a colder, closed off ML who's life is interrupted by the FL who is warm and cheerful. Due to the ML's carelessness, he ends up pushing her away and the two separate for years. When they reunite, the ML must work to win the FL back again.

Both are short dramas in which the ML and FL are forced to marry due to their families. ML is cold and distant to the FL but then genuinely falls for her.

Both feature a human FL who ends up living with the supernatural ML after she accidentally kisses him, swallowing his magical stone/bead.

Human/supernatural being with water related powers romances.

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Both dramas have "fish out of water" leads with water-related abilities/worlds who come on land to find their true love. The human they attach themselves to reject them at first but are forced to live with them and teach them about the world, only to fall in love.

Both dramas have a human FL who ends up "housing" the pearl/stone of the supernatural ML. While the ML tries to figure out how to get it back, the two end up living together.

Both are mini dramas with a human FL and a "fish out of water" supernatural ML connected to water who end up living together while ML tries to return home only for the two to fall in love.

Both dramas feature an alien ML trying to return home and a human FL with a connection to the entertainment industry.

Both are mini-dramas with an alien ML and a human FL with a connection to the entertainment industry. The two end up co-habitating.