Haven't watched my secret love yet but story seems pretty much similar..
-Multiple couples
-junior falls in love with senior
-junior is too shy to confess his feelings to his senior.

Haven't watched Sweet Prison but the stories are pretty similar the ML knew FL from past..
ML searches for the person who killed his family member.

-In both the lakrons ML is a Playboy
- Both the FL pursue divorce
-Both FL falls in love with another man who helps in getting divorce.
-The man who helps FL has their own diffculties.

-Both the main leads are in undercover mission.
-Both the dramas is about taking down drug mafias.
-Both the leads work undercover.
-Both have dramas have romance involved (less in NSG)
-NSG is more about drug mafias connection.

-Both the main leads are in investigation team.
-Both the dramas is about taking down drug mafias.
-Both the leads work undercover.
-Both have dramas have romance involved.
-Both the dramas are very good and each ep is connected to other perfectly unlike any other dramas which don't describe the people involved in it.
- Both have a time leap when the main leads didn't see each other for years

-Both the FL 's were defamed publically by a man.
-Both the FL have past which they were scared of.
-Both the ML help FL to get man arrested.

-Both ML's are genius
-Both ML's need everything to be perfect
-Both ML's are involved in amnesia theme
-Both FL's pretend to be in relationship with ML todave herself from miseries
-Both FL's hate ML for their bossy nature
-Both have boss employee relationship
-Someonw artempts to kill ML

-Both ML are dead.
-Both ML's duty is related to death of humans.
-Both ML are deadly handsome and my favs?
-Both FL struggle to live.
-Both FL always try to protect their loved ones.
-Both ML were heartless.
-Both female leads have certain no. of days they will live until they die.
-Both leads live together.

-In both the dramas modern life is connected with the ancient story.
-Both involve supernatural powers.
- In both the ML have a long life.
-In both the ML are in search of FL.
-In both the FL gets incarnated.
-In Both the dramas FL doesn't remember her past life.

-Both FL's hate ML at first
-Both ML's ex- girlfriend becomes FL's father's girlfriend
-Both FL's try to stop father from dating that woman
-Both FL's keeps on creating problems for that woman
-Both ML's ex-girlfriend are celebrities