>>1322588I'm sure this'll help, then: she's regarded as something close to a god, having the extremely vague (and thus, extremely unfair) power to manipulate boundaries of all kinds (in fact, it probably surpasses the abilities of the setting's handful of other dieties). Her manner is mysterious, frequently teasing, and constantly shifting from almost-sinister to almost-benevolent. She's notably fond of the setting's heroine. Fans interpret this to mean that they're getting it on. Then again, Touhou fans interpret a lot of things, but again we're talking about the popular vote here.
By no means the only example of fetish fuel in Touhou, but one of the foremost.
Also, damn yeah. Women in old-fashioned classy dresses are kind of rare, it seems.