Why
Sometimes people ask why I adore Shin so much, and It’s usually fairly obvious (to me at least). Shin is one of those growing character in NANA, and he progresses a lot from when he first joined in band. Although he posses that childlike demeanor, he’s still so amusing and lovable that you can’t help but want to hug him.
Shin is extremely hard to grasp; he’s not predicable like Nana or Hachi, you can’t expect to know what he’ll do next. He's one of those people that can get away with saying the weirdest of things and still pull on a straight face.
There’s strength to Shin that’s hard to understand. Somehow, it’s often implied that he is actually extremely mature, and we see that through out the manga as he progresses as a character. Unlike Nana who has gone through extremes, Shin is still young. Throughout the manga you see him in confusion as he comes to a realization of his feelings. You can’t possibly understand or imagine what goes through Shin’s head, and yet he still manages to pull up looks of rejection and disappointment to aid to his melancholy side.
Shin is one of the characters that have suffered through many things to get where he is now, and even though this might ben common among the charactersof Nana, he still has the strength to go on despite all of his love for Blast. It's true that Shin still has many developing to do, but as of now, he's already such a complicated character that it makes me not want him to chane anymore. I think, someone who has the ability to stirr up such an emotion is a worth character, no matter if he is considered as "minor" or that his love affairs are "frivious". The fact that he understands his situation and has already accepted it is one of the reasons that make him such a strong character.