In Hugo, there are three characters.
Hugo(moth man), Desma(the girl eith black hair), and Celestine(the girl with light hair).
I'm not really sure about the main character because first, I thought it was Hugo, but at the end, I thought it was Desma.
Desma and Celestine are friends, but at the same time, they are rivals.
They both want the prize for the Entomology project.
It looked like Desma fell in love with Hugo.
First, I thought the story was about Hugo, but after watching the film, I thought that the main theme was friendship.
Desma couldn't think about anything else but the prize, so she didn't care much about people around her. As a result, she made Hugo suffer, and almost made him die, and she lost a friend.
Finally, before the contest, she noticed what she was doing, and thanks to Celestine's help, she managed to help Hugo.
I think the producer of this film wanted to tell us that we always need to think of others.