Junghwan rescues a nerdy female classmate, Eunju, from drowning in a lake during his High School Senior Class trip, but he forgets that no good deed goes unpunished. While serving in the military, he encounters her again when she shows up to spend time with him while he's on town pass. After getting Junghwan drunk during supper, Eunju goes spends and evening going through quirky seduction tricks to try and get the man she idolizes to sleep with her.Fast forward a few years years and Eunju is a savvy, but still dorky, court prosecutor, and Junghwan is a college student, mooching off of, and occasionally stealing from, his eccentric parent to support himself and his best friend as they embark on sprees of rinking and womanizing. Unexpectedly, Eunju forces her way back into Junghwan's life to tell him that he is the father of twins, Dae-Han and Min-Guk**, as a result of their one night stand. Junghwan's parent's insist that he do the right thing and marry Eunju, and after Junghwan's mother bribes with a pile of cash, he does! Now Junghwan finds himself saddles with the responsibility of fatherhood, and strain of a marriage made up of a distinctly one-sided love. This leads to a comically escalating battle of the sexes as Junghwan and Eunju play increasingly cruel tricks on one another, which culminates with Junghwa having to make some important lessons regarding life, love, and unexpected fatherhood.**Dae-Han-Min-Guk is the Korean name of South Korea