Both main characters are switched their soul accidentally because of falling and related with the moon. And the good character poorly move her soul to the body of the bad one.

In "Tengoku to Joigoku" drama, the female lead that working as police, landed her soul on the criminal body that did many crimes and hated. But in the end.. same like "Switched" drama, they have to work together to fix all the issues and switch back their soul.

It's about time traveling to get the one you love through old photos that taken in the past.
But Proposal Daisakusen is a romantic comedy, so the story is more entertaining. However both drama bring a meaningful message about love and how important to appreciate and protect the person that you love.

Both drama have a romantic comedy office romance with the Male Lead as CEO / boss, and the female lead as a consultant / partner. But Hitomonchaku is more realistic and sweet, when Koi wa Deep Ni is more fantasy and romantic. However both drama give us some meaningful lesson about work and life, also have "tsundere" moment from male lead.

Both are telling the story about infidelity between couple, also age gap, older woman-younger man relationship. Both drama's genre are mature drama. In both drama, the main couple decide to be separated and at the end, both story are ended with an open ending for the main couple.

- Both drama have Tsundere male lead
- Both drama have a kind and strong female lead with publishing company background
- Both drama female lead admire the male lead's work achievement
- Each episode deliver about daily office work and colleagues interactions
- Both drama have a very succesful and rich Male lead and hard working female lead who chase after her dream
- Both drama have male lead who secretly become an online friend with the female lead
- Both drama have male lead with trauma from the past
- Both drama have lovely drama ost

Both drama is about a female lead go to comic world and meet his ideal boyfriend there. However in W, female lead is real human being, meanwhile male lead is a comic character.
In Lost Romance, both male and female leads are human being in the first place, they are just accidentally go inside a comic book, because both in comma state. So it's more like their real body still remain in the reality, it just their spirits move to the comic story.

In W (korean drama), the story is more like magical from the beginning. If you are looking something more fantasy with super villain and heroic actions, also teleport things between real world and comic world, then just go watch W drama. But if you are looking for a story that focus more to romance, then watch Lost Romance (taiwanese drama).

As you can read from both drama title. It describe about time travel or the life paralel universe. Both drama shows the main leads begin to date and enjoy happy days together, but then the secret and mystery are revealed bit by bit.

Both drama tell you about the time travel concept with romance and thriller as the genre.
Both drama will make you confuse at the beginning with the gloomy situation of the main lead. Then slowly but sure..the facts that they want to change are revealed. Both drama shows how the main lead try to protect their lover through the time travel. Also, the most similar part is about psychopat act that later on can explained how it will give big impact to the critical situation in the past.
And no matter how many times the main leads try to go back to the past, the future result is getting worse than ever.