Season 1
Kong Ji Hyeok works as the leader of the Mother TF team at a baby products company. He is sharp, calm, and executes passionately. One day, a team member, Ko Da Rim, suddenly kisses him. This places him in a difficult position because she is a married woman. Meanwhile, Ko Da Rim is a single woman who needs a job to support herself. She gets a job as a temporary employee at the baby products company where Kong Ji Hyeok works. She lies about her background and states she is married with a child to get hired there. She now works under Kong Ji Hyeok on the Mother TF team. Her only interest is to become a permanent employee there, but she begins to have feelings for Kong Ji Hyeok.
Nitric Acid, Sulfuric Acid, and Dynamite
Ahead of her sister's wedding, Ko Da Rim heads to Jeju Island, where a sudden encounter leaves her reeling — until she meets Kong Ji Hyeok by a cliff.
Gone With a Kiss
As their ruse turns into a real spark, Da Rim and Ji Hyeok go on an actual date. Meanwhile, Da Rim's mother collapses after a shocking confrontation.
Ping, Pong, Ping, Pong
Da-rim and Ji-hyeok's unexpected reunion at work takes a tense turn when he learns of her "marriage" — becoming a ruthless boss as punishment.
His Black Card
A tense escape from loan sharks brings Ji-hyeok and Da-rim closer, reigniting their spark. Later, Da-rim makes a heartfelt plea to keep her job.
Go Da-rim Is Mine! From Head to Toe!
After Ji-hyeok pays off Da-rim's debt, he starts meddling in every part of her life — leaving her torn between frustration and affection.
Swayed, Driven Mad
After witnessing Kim Seon-u's apparent romantic rendezvous with Yu Ha-yeong, Ji-hyeok debates telling Da-rim while caring for Da-rim during her illness.
I Want to Get Married, As Soon as Possible.
Ji-hyeok and Da-rim's bond deepens as they team up at a company event for newlyweds. Later, Da-rim falls in the mountain amid an unexpected crisis.
Love Is Hell
News of Ji-hyeok's engagement shocks Da-rim — and his coldness only deepens the hurt. A company trip soon forces them back into close proximity.
Don't Go. I Don't Want You to Go.
When Ji-hyeok learns the truth about Da-rim, he feels relieved yet deceived — and his unpredictable behavior pushes her to confess everything.
The Reason I Like You
Da-rim grows wary of Ji-hyeok's constant affection. Later, when their mothers gather at Seon-u's home, Ji-hyeok's competitive streak flares up.
Master of the Poker Face
After a confession, Ji-hyeok and Da-rim begin a secret romance — but not without close calls. Meanwhile, someone at work learns that Da-rim is unmarried.
Very Sweet
Racked with guilt, Da-rim decides to resign — but Ji-hyeok won't let her go. When a colleague catches their affection, Da-rim decides to tell the truth.
Flirting Master of the Orchard
After being forced to admit she was spying, Da-rim says goodbye to Ji-hyeok before disappearing. Heartbroken, he focuses on clearing her name.
Dynamite Kiss
Ji-hyeok makes his final move to take down his foes, but a vengeful act puts him in danger and erases his memory. Can he and Da-rim find happiness?