Both have the main leads being able to feel each other's pain due to the strange circumstances that brought them together.
They give similar feelings when.. the female lead has period crams and the male lead stays in bed (out of pain).. etc.

Both are romantic dramas, which deal with:

- a comic/novel/drama being an actual world for the characters living in it;
- a second female lead trying to overcome her terrible destiny;
- a virtual NPC trying to encourage the change into the script
- the female lead finding her love within and both of them fighting to overcome the rules of this world and death eventually

An overweighted housewife makes a transformation (through weight-loss) as one of her steps to get revenge on her unfaithful husband.
Dramas about her taking revenge on him.

Both have a plot in which a fictional for us novel or drama series are an actual world for the heroes who lives in it.
A heroine with unfortunate future fights from within to change the ending to her likings.

A female outsider enters a parallel world by mistake (or not so in MP) and tries to implement her absolute rights as one of the creators of this world in order to change the end result.

They have a similar premise..
A drama world's is like a parallel world.. then..
An outsider enters one of the character's body inside of the drama (in the NLWY there is a mix-up and a supported heroine acts as a main character ..while in MP the entrance is on purpose) and changes the heroine's actions in the way she would like it to be.

Both have female leads.

Both have a possible romance storylines between a secretary and her boss (former or not).
Both juggling with work-related company issues.
Both male leads have a terrible temper.

Both have two handsome males of similar age which fight one towards another and one woman whom is in between them.
"The good guy" is not really that good.. whether he is more of a vigilante.. or a person with a nasty charachter.. and the actual good guy turns out to be bad..only so that he turns out a new leaf at the last moment.
Both have manager and company schemes.. and a gang of staff..

The female lead is a strong woman with her own believes and is hardworking. Her romance with the second male lead is more of a forced one and she puts an end of it, but he still has a great admiration of her at the end.

There is a possible romance between both leads..never on screen.

Both have a male protagonist who is a bit of an asshole and his female subordinate who tries hard to tolerate him even thought his impossible character.

Both involve a possible romance between them.

Both are romantic comedies about a girl which is invested into creating romantic comics, but her career is about to fall down the drain, because her editors and readers doesn't think she understands romantic..

Then she meets the male lead and her drowning style starts to change.
Both male leads are very attractive to others and pursued by many..,but staying loyal to the girl.

Both are BL dramas that include romantic relationship between a professional debt collector and someone who owns a great deal of a debt.

Two boys are being put to live together by a "crazy" male parent. The newcomer being falsely as "cousin" or "brother".. it's suppose to help the attitude of the other guy so that he improve in his scores/studies.
At first they don't like each other much.. later they become each other's most important person.

Both are very light bl series on the verge of bromance or maybe even the opposite.