She's a third generation heiress of the second largest conglomerate group in Korea.

He's the first and youngest elite S-Ranked butler in the country.

He waits on her every need and more, but things change when she starts waiting on him.

Ha Maerin looked just like any other ordinary university student. She lived in a modest apartment and attended a public university. She even wanted to work a part-time job but she just wasn't allowed to. Because in the reality she tried so hard to disguise, she was a third generation heiress of Ha Enterprise of Arts & Redefined Trading, or HEART for short. It's not that she had anything against her family or the business. Not at all! In fact she was very loving and filial. She would gladly inherit the business that her grandfather had poured his blood, sweat and tears into. It's just that growing up being known as the insanely rich girl attracted a lot of unwanted attention to her.

Besides, she wasn't exactly the rich one per se. It was her parents. She was just, like any other child, getting allowance from them. Though it was true that her allowance was a little too unreal. Maerin never understood why they had to give her so much. They gave her a car, wouldn't allow her to work a job or rent a place, made her live in one of the apartments they owned and even paid her utility bills. After all that, all she needed was enough money for food, not another car. She understood that they did it all for her safety though. So she complied with the one condition which gave her masquerade the perfect look, no staff. What she meant? No chefs, no maids, no bodyguards, no chauffeurs and certainly no butlers.

Basically being a combination of all four, Maerin had the impression that butlers were utterly overbearing. She thought she'd never be able to handle having one. But she just might change her mind after sometime.

Lee Taemin, better known as Butler Lee, is a skilled young man who was raised his whole life in the British Butler Institute being taught how to wait on others. Achieving the world renowned 'S-Rank Butler' title, at the young age of 17, he was Korea's first and only S-Ranked butler at the time. He was surely sought after but only the best of the best could afford to get their hands on him. That being the HEART group. He served the group's founder and chairman, Ha Joong Sin, a caring man who took care of his butler like a grandson. If there was one person in this world Taemin could trust, oddly, it would have been his boss, Mr. Ha. The orphaned boy would have taken the man as his grandfather if he hadn't known his own limits as a butler.

Even if Mr. Ha insisted it was okay, Taemin would follow his principles as a butler and never bring himself to it, or at least he thought he wouldn't. However, you can't never stop your heart from feeling the way it wants no matter how much your brain thinks otherwise. That was the reason why, when the Chairman Ha passed away 6 years later, it hit him. He finally came to terms with the fact that attachment wasn't something you could control. It doesn't matter how you think you feel, you don't have much control over your heart.