I think they're referring to characters with that hair color in general. The "princess" part means Kaguya. For the most part these seem to generally apply, but in no way not involving literal-minded puns is Cirno cool-headed, mysterious or especially taciturn.
Edit: Just so you understand, I know that's Nitori, not Cirno.
ToshiakiAlso, Silver: Master's dogYou blue ones are black-hearted back-stabbers!!Stop Right There, You guys!Image file name:What about green?ToshiakiThe relationship between hair color and personality in Touhou series:
Black (or brownish): princess, pure and innocent
Red (or pink): boundlessly cheerful, earnest, spunky
Blue: cool-headed and taciturn, mysterious
Blonde: high-maintenance, tsundereNo way, you pink ones are just the sluts.ToshiakiToshiakiReturn to HomeToshiakiToshiakiGrrrrrrrrrrrrrrrrrrrrrrGreen: headcaseToshiakipost #1264667post #1414463post #1227314post #1264638