Soulmate AU where you have a timer on your wrist that's counting down to the exact moment when you first touch your soulmate.
Elaboration: Some people may not notice when their timer goes off. Imagine sitting in class, your timer almost at zero, and then it finishes counting down right as you feel a tap on your arm; someone's asking for your pencil, and you can't stop smiling at them, but they're just confused until you point at your wrist.
If your soulmate dies before you touch them, your timer is frozen at whatever point in the countdown it was at for the rest of your life. For example, if you had 3 minutes until you meet them, but then they die, your clock will be frozen on 3 minutes forever.
EXAMPLE SHORT STORY:
TBC