Black Butler (2014)

Both movies are about a noble lady & a butler. Both movies are very similar.................................................

Fang Jia Hua is the successor of a business. His dream is to open a chocolate store and be an expert in chocolate. He ends up leaving his business and his family to fulfill his dream. Hong Xi En is someone who spent her days slogging and taking up part time work. One day, she ends up working for him and above all, she has to dress herself as a man for the job.

Both FLs are human and MLs are a demon who are bound in some way to the FL. In both, there are mysterious crimes taking place.

Good romance. You have *bo-shan's* and main caretaker instead of butler. Shes gonna suffer for accepting to be a babysitter to BIG (adult) baby's. Worth of watching X"DDD

Both are about a person making a contract with a demon, selling his soul, in return for working with, protected by the demon. Both are based on famous manga.............................

Mizushima Hiro plays a butler in both. Kuroshitsuji is a movie and more dark than Me-chan no Shitsuji but both are good and if you liked his acting as a butler you should give the other one a try too.

Both MLs are powerful supernatural beings who make a contract/deal with the FL that is supposed to result in destruction (of the world vs. her soul).

Both are fantasy movies set in Medieval Europe. Both are based on famous manga................................................................................................................

Both movies are about demon MLs who have a contract of some sort with the human FL who is much stronger than she first appears.

The moment I saw the title I thought of Black butler - manga and anime. It is obvious that robot from Eternal butler wears exactly same costume as Sebastian from Black butler. Also the whole idea of a bit morally gray supernatural personal assistant called butler who also works in not obviously main character's best interest is exactly the same. Actually Eternal Butler feels like a sci-fi AU fanfic of Black Butler.