My Ex-husband Is 18

At 27, Yun Ha Rin meets her end in the flames—betrayed and nearly murdered by her husband, Kang Si Wu. But when she opens her eyes, she finds herself back in her high school days. With the resentment and thirst for revenge from the brink of death still burning inside her, Ha Rin vows never to fall victim again in this life. Yet the Si Wu of the past still stands before her, and unexpected events—different from her previous life—begin to unfold one after another.

Synopsis: MyDramaList