At first I was like, darn, all my MCs have normal hair colors.... then I actually thought about it for a moment. I had forgotten my own characters' hair colors... Finny has bright red hair (I like to think it's a rose or crimson red, but I leave it up to the reader to imagine it). Victor has dark grey hair, which is only weird because that has always been his hair color (he's not even twenty yet and please correct me if I'm wrong, but grey hair is uncommon in the young). There is also one major character (I won't say who because it's a spoiler) who has two really different forms, one of which has kind of a shade turquoise or aqua colored hair.
All of them are naturally that unique (as hair dyeing isn't really a thing for them... other cultures might use magic to do it, but none of these characters would think of that). Reds and greys are just common enough that people only sometimes take notice. On the other hand, blue is unnaturally uncommon for their society (not so much for the magic rich cultures, such as fae communities), though when it that form, I don't think their hair is the only eye-catching thing about them. Finny loves his hair color because it's as passionate as his personality. Victor.... well, I don't ask Victor any unnecessary questions. He seems pretty neutral towards his hair. The blue haired character was raised to be ashamed of their "unnatural" form, so their feelings on their hair color changes throughout the story.
Thinking about it, Dewi from RomaMates also experiments with unique hair colors. It's been red, partially red, partially purple, and even multi-colored. He's a model so he has fun trying out different styles and looks.
