If you are looking for a drama where the leads are in love with each other without anyone coming in between them, then this drama is perfect for you. The things I liked in this drama:
i. The leads: Their chemistry and acting is very real that you'll really think that you are watching a real story. The FL is soft and very strong mentally, doesn't break off easily and is very understanding to the ML. The ML is rough but behaves so calmly in front of FL and never has he disrespected her in any ways. No misunderstandings and no evil characters will break them off. They totally believe in each other and they only have eyes for each other throughout the series.
ii. The story progression: The story flows naturally from the time they both had gotten into the accident and then they fall in love with each other.
iii. The casts: Not only the main leads but the support casts are also exceptional in their roles especially the grandmother, the ML's Noona ,his brother and sister, the CEO and his ex gf and the director.
iv. Music: The music was perfect for the drama with right emotions at the right time.
v. The melo portion of the drama: The emotions were just right and you'll cry a lot in this drama especially the acting will make you fell the pain in real.

Lastly, I would like to say that do not miss this gem as it is one of a kind with perfect emotion and execution. I wish, in some world or some dimension there is Kang Doo and Man Soo continuing their story, living happily with each other as well as the other supporting casts, growing old together and loving each other unconditionally.