One of my favorite webtoons! The art is beautiful, the character's emotions are well thought out and presented, and the progression was smooth with supporting context that justifies each character's behaviors.
Some people complain about Hana's immature anger, or Shin-ae's unreasonable actions (from shunning Hana to the choices she's made afterward) but they were high schoolers who were prone to doing regrettable things when they are faced with a situation that leaves them feeling cornered. Even as they grew into adults, it's completely reasonable to leave traumatizing things in the past instead of seeking to dig it up for closure. It's realistic. I got chills during the flashback where Hana's anger dissipated into desperation when she begged Shin-ae to not hate her, because it reveals what we all probably felt at some point in our life. You want to protect your own heart by projecting hatred onto someone that hurt you- whether it be a lover or a friend, but you're simply hiding your own weakness. It's easier to try and hate someone than admit that they've made you miserable, yet you still care for them deeply.
Another favorite scene of mine was where the author reveals the last conversation Shin-ae had with Hana before she disappeared into a coma. She asked about her family, friends, and inquired about how Hana felt towards her. It was a small exchange but touched my heart so deeply. You meet and fall out with many people in your life, and it perfectly resonated with the feeling of curiosity that you would feel for an old friend or lover. These mundane questions feel so interesting, now that you are no longer a part of their life. I can't explain how well these interactions were written.
It was a great balance of suspense, romance, comedy, and thrill. The plot was unpredictable and kept me on the edge of my seat! Just as I was almost sure that they've correctly identified the culprit, the story would take another turn. Stories that compensate for a loved character's happiness for an interesting ending have a problem with feeling ingenuine, incomplete, or sloppy. The ending to this story was gracefully done and perfectly bittersweet. My heart aches for all of the characters who felt some kind of loss, helplessness, or betrayal- but I couldn't ask for a better way to finish this series.