Heaven's Demon - Purinz

The results of Huh Yunjin's investigations upon her suspicious colleague hit her straight in the face when she discovers that Kim Chaewon, one of the new hires at the law firm she works at, is a real life, honest-to-God, literal demon. Who also happens to be sinfully attractive and relentless in her pursuit of Yunjin.
Things get increasingly more complicated when, despite her persistent efforts to subdue her irritating libido, Yunjin gives into her temptations and lets herself reciprocrate Chaewon's advances.