It's honestly embarrassing how many times I have watched and re-watched this show; the actors are amazing and their haters to lovers plot is executed so well. They have great chemistry and they really do just feel like two university students which I think a lot of kdramas can exaggerate sometimes. This drama came out in 2016 but nearly everyone I ask that is into kdramas has watched it and loved it. Simply put, its a really comforting show to watch and they deal with some difficult topics as well.
I think my favourite part about the show is that Kim Bok Joo never has a "glow-up" moment where she miraculously becomes this gorgeous girl but she just is herself throughout the entire show and she is loved for that. A lot of other kdramas can't say the same.

Be warned, you will want a significant other after watching this.