This is actually a drama I just recently finished and wow.
I really wasn't expecting to like it this much, but it really didn't disappoint!
Im usually a sucker for time travel kdramas and this one..wow this delivered everything and more that i needed.
The regret of changing the past, how the smallest things can change the biggest outcomes in your life, and what i rellay found unique is how they didn't go back to their old life yet they actually used this time travel to their own benefit and found a way to be happier than when they were before the travel.
It teaches you a lesson that your fate is written with a certain person, and they are simply your soulmate and you can't do anything to change that fact!

Really recommend this! It will not leave you bored!!