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.
Ling Qi Sa is a man who is buried by his parents' gambling debts. With no way to pay back the money, he thought about going to the dark side by getting into the kidnap and ransom business. But instead of becoming a kidnapper, he ended up saving a girl from a real kidnapping. The girl turned out to be the sole heir of a conglomerate who faced these kinds of threats every day. In a case of a kidnapping gone wrong vs. a mistaken love confession, she hires him to be her butler and helps repay his parents' debts. Grateful to have gangster collectors off his back, he vows to protect her from harms, which is no easy task.
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.
