Ongoing review (See final update after completing it at the end):

It is overrated here. This does not compare to other good romcoms and definitely doesn't compare to Love Like the Galaxy or even Who Rules the World. I have watched up to ep 15 and it is below par with the top Chinese romcoms dramas. I like Lu Si and I have seen most of her dramas but her acting as a 17-year-old made me cringe, by skipping like a child in one scene, and constantly hugging a stuffed animal... Etc. which is appropriate for maybe a 12-year-old. The grade school SZ was more mature (played by Zhang Xi Wei who did absolutely wonderful, by the way). After episode 1, I was really looking forward to her character growth but it actually goes backward. Their actions and banter are still like 14 or 15-year-olds even in episode 15. It has been the same type of interaction. It is repetitive. Episodes 12 and 13 gave me hope to show some depth but it fell back to the same pattern in 14 and now 15. The best part about this drama is her interaction with her brother and their relationship but those scenes are far and few between.

It is extremely slow and uneventful for the majority of the episodes with most of the drama just interactions between the two leads. I am still sticking with it but I find myself struggling to keep interested because the script is way too simplistic with no wit, no humor, and no memorable lines... Etc. and pretty unrealistic for college-level romance. It feels tedious. I will update this review if I change my mind.
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Final Update: Even at Ep 17 there was still the same type of dialog "Do you really have no feelings for me?" "Maybe just a little bit." >.< There are countless scenes throughout this drama of making a big deal about this age gap of him being "old". Not sure why the director/writer emphasized it as much as they did. Again, I think the show should've had far more scenes with the brother and their relationship instead of the slowing moving repetitive interaction between the leads. It's cute and all but 25 episodes of that was just far too slow and tedious for me. I think most people would be far better off spending time watching the modern drama Reset, or if you are into romcoms Meet Yourself, The Love You Give Me, The Day of Becoming You, Skate to Love, and more. If you like costume dramas, then there are plenty that are worth your time.

Final words: Having said that, If you like this type of drama then try it. Everyone is different. For me, I just didn't care for it. Too simplistic for my taste. As I said, the best part is episode 1 with the child actress and the rare parts with the older brother. But then it goes downhill. I favor Wuxia like Nirvana in Fire, The Untamed, and Joy of Life (so I may not be the best judge for this type of drama) but I do enjoy romcoms from time to time but there has to be some comedy, and memorable lines, or wit, and more depth for me to really embrace it.