You just made a contract with the devil to turn back the time to prevent the death of your boyfriend. Of course, the offer isn't free. Going back 20 years ago will cost you 50 years of your life span. That's more than double the years you asked.

Then, the time came and you agreed to the offer. You woke up and looked at yourself in the mirror. It worked, you are back as 18.

You looked over the whole town and finally found him again. He looked at you with an innocent smile.