The complicated hero is a round character; the sidekick is a flat character.
You can describe them as "needlessly complicated".
You describe them the same way you describe any other characters in your story. Click the link to learn how to describe people.
The word that describes a complicated layout of paths is "labyrinth".
describe each of the characters and their relationship with one another?
This is a "round" (complex) character.
This is a "round" (complex) character.
notorious
honest, transparent, forthright, straightforward, genuine, uncomplicated
Intellectual, Peaceful.
doodlehead
The same way you describe anyone! Here's a link to that question.
Here's a link to show you how writers do this.