Kairos

Living a precarious life as a part-timer at a convenience store, Ae Ri works to support her mother, who is on a waiting list for a heart transplant. Unfortunately, her mother's physical condition worsens, leading her to forgo the long-awaited opportunity for the transplant, yet just like that, her mother disappears. Things were already chaotic enough for Ae Ri, and then she receives a phone call from a strange man claiming he's 31 days in the future.