Sarasah

Sarasah is "about a modern young girl who's desperately in love with a boy, but this boy really hates her. He accidentally pushes her down the stairs and she dies. But when this newly deceased girl shows up in the afterworld, she finds out that it wasn't her time to go yet, so the powers that be offer to send her back to the land of the living. Her goal for this second chance at life? Go back in time to make this boy fall in love with her."
Ji-Hae has a crush, but when she confesses her feelings, Seung-Hyu pushes her away — literally! After plunging down a flight of stairs to her death, she’s told in the afterlife that it isn’t her time. Empathic that she would rather die than go back to face rejection from Seung-Hyu a second time, Ji-Hae is granted an opportunity to travel into the past to mend this relationship in a past life. To get close to Seung-Hyu’s past self, Ji-Hae disguises herself as a boy and joins the Hwa-Rang, Korea’s elite archery squad — all of whom are bishonen!
No one said the path to true love would be simple…