One fun fact about the characters' designs is that the main character's outfit was inspired by the fashion of the 1920s, with a modern twist to make it more appealing to a contemporary audience. Additionally, the colors used for the supporting characters were chosen to reflect their personalities and roles in the story, with warm tones for friendly characters and cool tones for mysterious or aloof characters. The intricate patterns and details on the costumes were also carefully designed to add depth and visual interest to the characters on screen.