Do Bong Soon (Park Bo Young) is a young woman born with superhuman strength, who breaks everything she touches if she's not careful. However, she desperately wants to become a willowy and elegant woman, which is the ideal type of her crush In Guk Doo (Ji Soo).
Thanks to her strength, she gets the job of a bodyguard, to a spoiled rich heir An Min Hyuk (Park Hyung Shik), the boss of a gaming company. Opposite of Guk Doo, Min Hyuk is a crazy and odd man who is imperious and has no regard for rules.
One day, Bong Soon, Guk Doo and Min Hyuk gets caught up in a serial murder case that breaks in their neighbourhood, and end up reluctantly living together for security purposes. A series of misunderstandings occur when Guk Doo mistakes Min Hyuk's affection.