Jang Sun Kyul sufferes from mysophobia and operates a cleaning company. He meets Gil Oh Sol, who has a bright personality, but does not mind getting dirty. With the help of Oh Sol, Sun Kyul faces his fears and falls in love with her. Meanwhile, Choi Koon is a mysterious man who lives on the rooftop of Oh Sol's house and is known for being a free spirit.
E1
While looking for his beloved robot vacuum, fastidious CEO Jang Sun Gyul runs into Gil Oh Sol, a job seeker who doesn't mind a bit of untidiness.
E2
Sun Kyul gives Oh Sol one week to pay for damages. Growing more desperate, she decides to apply to one more place, where her skills may come in handy.
E3
Oh sol runs into Sun Kyul at her new job. When he later finds her drunk on the street, he reluctantly gives her a ride home, but ends up regretting it.
E4
Sun Kyul wakes up in the hospital but has no idea how he got there. Oh Sol tries to comfort her father and astounds everyone at work with her new look.
E5
Sun Kyul makes a rash decision that he soon regrets but keeps doing things he can't explain. Oh Sol is stunned to learn about Sun Kyul's condition.
E6
Sun Kyul becomes distraught when he learns about Oh Sol's new assignment, but can't get hold of her. Oh sol is bewildered by Sun Kyul's actions.
E7
Baffled by Sun Kyul, Oh Sol pours her heart out to a neighbour. Distracted at work, Sun Kyul comes to realize something -- but it may be too late.
E8
Choi Ha In's revelation catches Oh Sol off guard, but his words keep swirling in her mind. Oh Sol helps Sun Kyul during a precarious situation.
E9
Oh Sol grasps what her job means to her and resumes work. When she's falsely accused by a client, Sun Kyul defends her, putting the company at risk.
E10
Sun Kyul is puzzled to find Oh Sol at his place, but things get more awkward when his mom stops by, and he later sees changes at home and in himself.
E11
Oh Sol is perplexed by Sun Kyul's attentive behaviour. Sun Kyul panics when an unwelcome visitor arrives, and his mother later asks Oh Sol for a favour.
E12
Oh Sol keeps telling Sun Kyul that she's not looking to date, but he arranges an impromptu surprise for her and reveals another side of himself.
E13
Sun Kyul admits Oh Sol is the first person to be empathetic about his quirks, but she decides to move out after coming to terms with her feelings.
E14
Sun Kyul is resolute about curing his mysophobia, but Oh Sol reaches a drastic verdict after her family discovers his grandfather's identity.
E15
Devastated by his grandfather's revelation about AG Group, Sun Kyul discovers he's been betrayed by someone he implicitly trusted.
E16
Oh Sol hears that Sun Kyul is leaving for the U.S. Oh Sol's family receives an overdue apology. Sun Kyul wants to start over, but it may be too late.