This drama is brilliant in an incredibly sad and soul-crushing way. Honestly, if you're looking for a happy end, this is not it.
To be honest, I started watching this drama because I had a little bit of free time and I thought I'll just watch one episode and won't have a problem putting the show aside for now.
Instead, I immediately got hooked.
The episodes are written in a way that has you sitting on the edge of your chair, waiting for the conclusion while desperately trying to figure out what is going to happen yourself. At the end of every episode, I immediately wanted to know what would happen next and couldn't help but watch the next episode.
The way the main characters change throughout the drama, the way they start to think about thinks differently and how that affects their actions (or doesn't) is captivating and at times truley soul-crushing.
I can't get into this without spoiling anything, but I think you'll understand once you watch the drama.
The ending was very.... fitting and to a certain degree satisfying. While it is sad, it was the only proper end to this story.

The acting was immaculate. At first, I thought Ohno Satoshi might have been a little bit cold and stiff, but it turns out that said coldness and stiffness was intentional. He manages to portray Naruse's struggles perfectly and makes the audience understand, what Naruse is going through emotionally.
Serizawa Naoto seems like a very stereotypical character at first, but through Ikuta Toma's acting he became a likeable character that the audience can sympathize with, to a certain degree.

The music was very fitting and altogether good. At times I thought it was a little bit too dramatic.

I'm really not sure about the rewatch value. I don't think I will rewtach this drama, to be honest. Personally, I don't think I can watch Naruse and Naoto in the first few episode if I already know what kind of people they are in the end of the drama. Especially Naruse would be tough to watch.
I do think it has rewatch value though if you don't have the same problem as me.

To be honest, the only reason I'm not giving this drama a 10/10 is because at times it was a bit too melodramatic for me. Some shots (for example zooming in a character’s face twice from two different angels) just felt like they were trying to add unnecessary suspense and drama. It was especially unnecessary because the story, music and acting managed to build said suspense on their own.

I would definitely recommend watching this drama! You should just be aware that it's very sad and does not have a happy ending.