Ungyou

Dongsoo is parted with his lover after he witnesses her having a one-night stand with Inhan. To his surprise and dismay, the new laywer hired to his company happened to be Inhan, and they can't avoid running into each other at work. As a revenge for ruining his love life, Dongsoo seduces Inhan's partners and somehow succeeds each time. Inhan finds Dongsoo annoying, but somehow interesting in a way.