I'm making this a more general trope, like Rose-Haired Girl. Still, this isn't a dumping ground for purple haired characters, they have to fit one of the descriptions.
Animation uses impossible natural hair colors to help differentiate characters who who may otherwise look quite similar. Some of these hair colors are indicative of certain things about those characters. Purple hair is no different and is the intersection of two opposite hair-color tropes: Shy Blue-Haired Girl and Rose-Haired Girl. Violet-haired girls can favor either the passion of a Fiery Redhead, or the manner of a cool Ice Queen. Purple Haired Girls can be associated with royalty and all the things that come with it, including wealth, status, sophistication and sometimes arrogance. With this association they may be princesses, or act as if others should treat them as such. Being Posh, Vain, Snobbish or Superior are also common. On the other hand however, they can be Elegant, Modest, and Kind. It's essentially the difference between a Royal Brat and Princess Classic. It's not uncommon for such characters to have a Noblewoman's Laugh, or speak in a very formal manner. A Hime Cut, is also very common for such characters, the hair-cut itself one associated with nobility and royalty in Japan. Shrinking Violet, this is such a well known phrase in the west that often purple-haired characters in Western Animation will be meant to allude to it. In this case the characters may be a quiet Kuudere or Emotionless Girl, or have No Social Skills, fearful of interaction with other people. Peek-a-Bangs are a common associated hair style, as well as speaking in a quiet voice, or not speaking much at all. common Mary Sue trait as well. Why? Because it's cool and unusual, probably. Purple hair is also strongly related to Tall, Dark and Bishoujo, because Purple Is the New Black. As black is very difficult to render on screen, characters whose hair would be understood as black hair if it were in Real Life, may be colored purple. Likewise if a character has black hair in another media, when it is being adapted to animation it's hair may suddenly be purple. A Subtrope of You Gotta Have Blue Hair. Compare Shy Blue-Haired Girl and Princesses Prefer Pink. Contrast Rose-Haired Girl. Has nothing to do with Elderly Purple Haired Ladies.
Examples:Anime and Manga
- Hitagi Senjogahara from Bakemonogatari has bright purple hair in the anime, she has a very superior attitude and messes with the main protagonist's head for her own amusement, and is an Ojou and something of a School Idol.
- Yoruichi from Bleach, who is from a noble house and is treated like royalty by the servants of the Shihoin family, such as Soifon, but otherwise acts like more of a Rebellious Princess except that she's so competent it's less rebelling and more she just gets her way.
- Queen Nehellenia from Sailor Moon, who is a Queen, not to mention a very haughty villain. Sailor Mars has Shiny Midnight Black hair with purple highlights and happens to be The Ojou, as she is rich and goes to a private school.
- Konan from Naruto, who is the only Kunoichi in the Akatsuki and Pein's right hand girl, she is the Yamato Nadeshiko type.
- Faye Valentine from Cowboy Bebop has purple hair and is quite full of herself, and pretty much demands that everyone treat her like a refined lady, not that she acts like one.
- Tenchi Muyo! has Princess Ayeka from the planet Jurai, who has purple hair. Not to mention Tenchi's grandfather and her brother who also has purple hair.
- Henrietta in Zero no Tsukaima is a Princess, later a Queen, but more of a princessClassic, Yamato Nadeshiko type.
- Kyouka Kanejou from B Gata H Kei, who is an actual ojou as well.
- Himemiya Chikane in Kannazuki no Miko. Sometimes her hair looks dark blue and other times it looks straight up purple, but she is The Ojou.
- Natsuki Kuga from Mai-HiME another one whose hair oscillates between dark blue and purple depending on the picture.
- Ogasawara Sachiko from Maria-sama ga Miteru who is an Ojou, though most characters in it are Ojous.
- Sylia Stingray from Bubblegum Crisis, has the dark-blue hair in the original series, and light blue-hair that sometimes looks lavender in one of the newer series as well as being The Ojou.
- Anthy Himemiya from Revolutionary Girl Utena is an actual princess but she subverts most other princess tropes, except for this one.
- Dalian from The Mystic Archives Of Dantalion, who has Princess Curls along with her purple hair. She is a Tsundere who orders around a Lord and is herself a mystic library of lovecraftian-grimoires.
- Princess Eclair from La Pucelle.
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