This one became an instant classic for me, it's just that good.
To me this show is everything a romcom could and should be - the characters are believable and likable, the plot is compelling but does not take away from the romance, the pacing is well thought-out, and the romantic tension builds at a perfect speed.

But more than that this story has a deep understanding of not just its characters, but what being human means at large.
The characters are all vastly different personalities with their own unique charms and dynamics, but also each with their own unique set of flaws. They feel like real, actual people, and it is in that grounding connection to reality that the show really shines.
It makes the audience question things like "How do you deal with your life suddenly changing and starting down a path you never expected?", "What does loving someone really mean?", "How much are you letting the past control your current life?", and "What does forgiveness mean and whom exactly does it benefit?"

The show tells its story perfectly beat for beat and pulls the audience along on a ride that is in turns fun, emotional, captivating, and absolutely joyous. Add to that the lovely visuals, solid editing, and good music and you get a romantic drama par excellence.
I honestly can't think of any reason not to watch this show, I genuinely and wholeheartedly recommend it to any- and everyone. Go watch it already.