ML vs. FL sees ghosts and lives with ghosts who participate in his/her life and basically are like family.

Both dramas feature a FL who sees ghosts and lives with at least one, who is closed off to the outside world until the arrival of the ML who is supernatural or has supernatural abilities.

Both are short dramas with a ghost-seeing FL. The ghost ML vs. SML is not truly dead (yet) but is thought to be by the FL.

Both are short dramas with a very light horror tinge. In both the FL can see ghost(s).
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Both dramas have a richer ML/less well to do FL. The two have a childhood connection and shared trauma but don't realize it until much later on. The main couple ends up living together and fall in love.

The main couple have a childhood connection they don't realize/remember, the ML (or both) have suffered some trauma in their childhood. FL is employed by the ML/his family which requires them to live together and leads to them falling in love. ML's closest family (mother vs. grandmother) is determined to see him married and over-involved in trying to get the main couple together. Both dramas have similar pacing and feel. Also, the SML actor in PL is the ML of TTFIL.

In both, the main couple have a past shared trauma related to a death that affects them in different ways. They end up living together and slowly heal each other as well as fall in love. FL is employed by the ML/ML's family, and the ML is far more well to do than the FL.

Both dramas deal with trauma and the leads living together and healing each other.
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Both dramas begin with the FL searching for someone she met years ago who she intends to marry and can only identify by a mark of some kind (birthmark vs. a mark he draws). She identifies the ML as this person and begins following him despite his rejection and having no memory of her. Just as he's falling for her, she begins to believe someone else is the person she's looking for. Both FLs are forward, quirky, offbeat/unusual, and endearing.

Both dramas are about a rich ML with trauma entering into a contract marriage with the FL.
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MLs end up entering into marriage with the FL due to an agreement/debt between their families.
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MLs are rich CEOs with trauma who hire the FL (contract marriage vs. bodyguard). Both dramas have a similar tone and feel.