Who Are You (2013)

Soma Yui and Torino Naoki were childhood friends, but they met again as adults. Just as he decides to propose to Yui, Naoki suddenly disappears from Yui's sight after being embroiled in a mysterious incident. Naoki continues to wander in this world as a spirit without knowing that he has died. Naoki asks Uozumi Yuzuru, a detective who is the only one able to see Naoki, to convey his feelings to Yui, but Naoki ends up breaking up without properly saying "thank you, goodbye, and I love you" to the person he loves the most.

Both have a human lead living with/haunted by a ghost.
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Both feature a cop that sees ghosts and uses that to solve crimes and then eventually a mystery concerning themselves. GSDCY is darker and more serious than WAY.

Both have a human lead who is haunted by the ghost of someone they were close to/loved.
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watching Raak Boon every episode reminds me of Who Are You, because both female lead suddenly can see ghost and the ghost always appear before them to disturb them cause they need help, the ghost gives hint to our female lead to catch the criminal who kill them, and solve the case..
both story involve police and cases, i also think the character personality is quite similar too...

Both have male leads who don't want to get involved with the female lead in the beginning but are curious about her. In both dramas, the female lead keeps on getting into trouble but both are smart and strong, but she ends up dragging the male lead around with her.
I watched Who Are You? soon after Catch The Ghost had started airing and to be honest both have similar mystery and comedic vibes. But I feel the chemistry between the leads in Catch The Ghost is much better since its a tagged romance drama which is not in case of Who Are You?
Anyhow, if u like Catch the Ghost , I recommend Who Are You?

The similarities... Damn it i wont spoil you but you will definitely feel more about the second main leads. They are honestly the show stealers. Though the main couples are ok the sls is real. Especially all that doomed love theme about them...

They are both crime and suspense dramas. They both have one case that leads the next and ends up being an entire conspiracy. I mean they both have gorgeous leads and a little romance in them.

They both are crime and suspense dramas. The leads have amnesia. They have amnesia due an accident during a mission. Oh and of course they both have a little romance in them.

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 focus on a detective whom through an on the job trauma, can see ghosts and use their messages to solve their murders.

Both female protagonists got with a special power... and then help solve crimes using their powers.
Both female and male protagonists work together to solve difficult crimes, and in doing so, start to develop feelings for each other.

Similarities:
- Both use a supernatural way to solve crimes - and uses this element to make matters more interesting other than dragged out.

- Both share some kind of love triangle. (Have only seen until the fourth episode of "While You Were Sleeping" when writing this recommendation, so I could be wrong.)

- Both share some of the same genres. (Including Romance and Supernatural)

Differences:
- While "Who Are You" is set in the world of cobs, "While You Were Sleeping" is set in the world of prosecutors and lawyers.

- In "Who Are You" the main female protagonist can see ghosts/spirits of their victims while in "While You Were Sleeping" they can predict the future through dreams and strive to change them.

While different in setting and plot, both have horror. mystery, and romance as the genres and feature a ghost that haunts the FL because he loves her or wants to marry her.

Korean dramas about a lead who can see ghost(s). The plots deal with closure and moving through grief.