I won't be holding back on spoilers, because I need to specify why I feel this way.
I'll start by saying I was excited for this series because of Chap. I've liked him in his other works (Y-Destiny and Lovely Writer) but didn't like his love interests at all. So I had hope! That he'd finally get a good love story and have a role where he could shine.
And for awhile, it seemed that was happening and that Aioun would be a good love interest. I explicitly noted that Aioun was the only decent person amongst the central characters, but then his girlfriend showed up.
Jumping back, my biggest "Why?" in this is "Why did they fall in love?" Or maybe "when?" It wasn't clear to me at all where their feelings developed, and the unnecessary flashback in the final episode just showed more concisely the complete lack of development in their relationship. They went from being entirely hostile to saying that they really care for one another. What? Why?
Sichol sucked. I'm sorry, but he sucked. I was annoyed by him most of the time. Who lies to their boss on the first day? Not that Nawee was a good boss, considering he physically abused his employees, but Sichol deserved to be fired. Oh on the topic of violence, Sichol then knocks Nawee unconscious to essentially kidnap him despite knowing he has horrible agoraphobia. Said phobia was another thing handled poorly! Aioun says "you have to face your fears." to Nawee in regards to his debilitating mental illness. What? You suck! Not how that works!
Oab sucks. Who hides their brothers pet turtle and then gets mad when said brother gets upset?
This was why I initially thought Aioun was the only good person: he didn't lie to and manipulate others, physically abuse his employees, or lose his brothers beloved pet. But he did cheat on his girlfriend. And then refuse to be honest with her despite her giving him every chance to be upfront about his feelings.
Chanjao is great! She's mature and kind, and I feel horrible for her that she got stuck with someone who wouldn't just be honest. I'm glad to see a good female character, at least.
He did eventually break up with her, though he mostly just stood there and let her do the talking. What a jerk!

Nawee could have been a great character, because I felt a lot of sympathy for him with his trauma and familial issues. But you can't treat people like that! You can't throw things at your employees or punch them with an hourglass! He's entitled and rude, and his awful family doesn't give him an excuse for that behavior.
But really, when he wasn't being horrible I could almost forget what he did because he was a sympathetic and sweet boy. Chap did a good job with what he was given, which wasn't much unfortunately.
Aioun was kind, mature, and calm. Until he wasn't.
Most of the characters had their moments, but it wasn't in a profound "humans are complicated and no one is fully good or fully bad" kind of way but in a "this is a different character now" kind of way. Aside from Nawee's family, who were consistently awful, evil people.
There were good moments, but not nearly enough. It had a rather short run time, but that's no excuse for a complete lack of development in your principal relationship. It's at least some consolation that I didn't waste much time on this.
I couldn't fully enjoy the sweet scenes, because they felt undeserved. Especially after finding out Aioun was a shithead with a girlfriend he was cheating on.
Also! for the love of god stop putting the damned "trip into a kiss" nonsense. Twice they did that, and both times I rolled my eyes so hard I probably saw my optic nerve.
Contrary to my scathing review I didn't completely hate the show. I definitely can't say I liked it, but there were parts I enjoyed. Chap did a good job in my opinion, and hopefully he'll be able to get a main role again, but with good writing and a good love interest this time. Please.

The best part of this show was Jeff Satur. It's unfortunate that his beautiful songs weren't put in an equally beautiful series.