After the good ratings, I was really disappointed by the storyline.
This drama is a mix of settings and clichés you see in different dramas. I seldom see such a mix that is almost done like a recipe (s.u.).
ML actor saved the scene more than once. The music is fine, too. Just tells you which emotions to have without being noisy. The overall cinematographic quality is quite good, and the storyline is made for being popular.
If you like this kind of recipe, it is something for you, but don't expect really something new. Sometimes, you could really expect what would come next and just wait and see: it happens exactly that way.
I might have enjoyed it for just being a good drama. Not excellent, but good. But I kind of lost interest already with the second time jump. Why is it that popular for the FL to leave and become a different person, resulting in an "old flame" storyline? It is not really the same story, not even the FL we knew anymore. Never understood that. Also, I made the mistake to just want to watch the last episodes before going to sleep. Don't, if you want to sleep afterwards.

Recipe (spoiler alert):
- Take a rich good for nothing/bully and add a "tragic" past like dead parent or parent not there for him when needed.
Add a female, who does not fawn over him like everyone else.
- Make it a bet turn real love for the good-for-nothing until he wants to prove himself to the FL.
- JUMP IN TIME -> FL has a good male friend, ML is successful and overbearing (boss in city).
- Contract marriage turn real,
- salted with a jealous "ex-girlfriend"/trusted friend, a lot of misunderstandings, trust issues etc., similar story lines (FL acts, ML saves, ML jealous, FL angry) in a loop, until the FL can't handle it anymore and leaves.
- One more JUMP IN TIME. ML never forgot, FL comes back as a different person.
- Old flame, old misunderstandings get cleared.
- Fast-paced and tragic ending, turning the situation within just a couple of episodes completely.
The most creative part was choosing this setting int time (although not new, at least not as often as the other elements) and his parent's military power struggle (ok, untrusting superior, rival/enemy of same rank, mole - not too new either).
I have to correct myself: Most creative is mixing everything into one drama.