
a) Characters look the same. There may be extremely limited details that are different but considering there are so many of them and the updates are irregular, it gets tough to follow the story.
b) I get it. They're all psychopaths. But layering the story with so many issues is problematic. It's hard to follow the story. When it gets this hard, it's tough to keep rooting for it. Confuyaing flashbacks are great but with so many characters involved both in the past as well as the present.....^sigh^
And I really liked this story...

You are my only crane. You are my <cue title page> "a thousand cranes." That was pretty brilliant.

The Japanese refer to the crane as “the bird of happiness;” the Chinese as “heavenly crane” believing they were symbols of wisdom. The powerful wings of the crane were believed to be able to convey souls up to heaven and to carry people to higher levels of spiritual enlightenment.. Hope this will help a little bit

Yes. Exactly. Paper folded like the birds. The belief is that if you fold a 1000 cranes, you get a wish fulfilled. The subversion here is that he didn't need a 1000 cranes to get a wish. He pretty got everything he wanted in life with just one "Craig." Craig made his wish come true. So essentially Craig is his thousand cranes.
The twist made the story worth reading it. ^serious nod^ it'd have been boring otherwise.