Understandable separation

A little  drama ( not a real breakup) ,very necessary for showing their relationship. 

Time jump separation (necessary for the story)

Break up in the very start of their relationship but once they fully true to each other , there is no misunderstanding or any breakup.. ( that to at least 70 eps)

A little (kind of breakup)bickering or squabbling between a couple..(only because they want to protect )

Time jump separation ( necessary for the story )

Time jump separation ( as she is the mermaid, had to go back) but you will get to see nice , happy ending 

Very little separation (as she was the ghost) .. not painful or unnecessary, they reunite very soon and fight together.. great drama 

Kind of breakup ( just little fight between the couple, just to protect each other)

(Kind of breakup ) but fl shows the ml, what true relationship is, by standing next to him

Very little time jump at the end .. ( can be avoided) but it’s fine as they were always in touch with each other

Kind of breakup, but fl shows what true relationship is, by not giving up on ml

Kind of separation as ml is a liar and fl is hurt but fl is very mature to understand the relationship.

Little breakup because of his brother ( it won’t bother you much)

Little drama in the end 

Time jump 

Separation because he was on the mission 

Breakup is very early on.. before they start the real relationship 

Very minor breakup (you won’t even remember because ml make sure fl doesn’t go away)

No breakup but Separation because of time travelling, but kind of happy open ending ..  but still sad in the end 

Breakup to protect (little annoying) but ml was always there for her..

Two seperation, first is breakup because of his past, second separation because he is demon 

Separation are reasonable but still painful 

Little distant with each other for her dream 

Reunite story after a long breakup, but he was always there for her.. also, there is time jump separation in the end.

Little breakup ( in start of the relationship) but it’s understandable as fl though she is not mentally fine to start something new. Got together in next episode and never go apart.. happy ending