well-written & interesting characters

Each and every character has their own unique charm to them. If every character had their own series, I'd watch them all with no doubt. This story treats every character as a human being with their own life, yet still focuses the most on the main couple- THIS is the standard.

Mostly Win, can we get more main leads like him? 

Many characters in UWMA and BU seem bland, it might just be the actors not pulling their roles off but one of the few characters I didn't find annoying was Win. Boun set his heart out to act for this project and he outshined everyone. (except for Perth's guest role in UWMA... Literally, the only scenes that made me cry were the flashbacks with him in them... Excuse me getting sidetracked oops)

Astounding character design and cast performance. Dull characters? NONE. I absolutely fell in love with the way this plot uses the characters to its fullest. Morals aren't clear and that's true to life. Special mention to Sing's performance in this, he nailed Tod's personality.

The characters were so full of life and interesting, not to mention the acting... Gave me goosebumps! Many in the comments were contemplating whether Denis' character was useless or not, but I found him to be a very charming point in the story, his persona was what stuck with me the most.