It’s true that opinions vary, but the narrative involving shifting timelines and futures felt excessive and irritating. The plot never quite resolves itself, even within a fictional context, and it stands apart from other Korean series in a disappointing way. There's no sense of completion; you find yourself watching simply to finish, not because you’re invested. It seems like the writer lost their way, creating a rambling and ultimately tedious experience for the viewer. The soundtrack is enjoyable, and the actor portraying his character delivers a convincing performance, appearing genuinely naive throughout. However, the actress in the lead role occasionally overacts, while at other times her portrayal feels lackluster or uninspired. I generally appreciate Korean cinema, music, and related works, but this one was simply not good.

Source on TMDB