SarasahSarasa; 穿越时空再爱你; 사라사

From Yen Press: High schooler Ji-Hae is desperately in love with her classmate Seung-Hyu. She has done all she can think of to win his affection, but to no avail. When her latest scheme crosses the line, Seung-Hyu decides he’s had enough…and inadvertently pushes her down a staircase! Ji-Hae awakens in the world beyond, only to learn that it’s not her time to die. But why go back when the love of her life hates her to death? Touched by her passion, the keepers send Ji-Hae to her past life to mend the rift between her former self and Seung-Hyu. But can Ji-Hae keep up the act long enough to find Seung-Hyu and set things right?