Touhou Patchouli Knowledge is a smart magician (witch) with long purple hair and eyes, and wear pajama-like outfit. Althoug she is not the leading characters of Touhou series, she is quite popular, with no exception of cosplay. Obviously, one of the main reasons is that Patchouli Knowledge is really cute and beautiful; hence, cosplay girls could become very enchanting when dress up as her at shows.
And this pink Scarlet Weather Rhapsody Patchouli Knowledge cosplay costume is one of the typical pieces, which is in the form of pink and white long sleeves ruffle dress with big white ruffle collar, red bow at neck, two red bowknot at the bottom of each side, pink ruffled cap with bow and yellow moon pattern. It looks the same as the one that Touhou Patchouli Knowledge wears and would make cosplayers become pretty cute.