Easily one of the most enigmatic characters despite appearing in so many games, Izayoi Sakuya is the Chief Maid of Scarlet Devil Mansion who has the power to stop time. Her ability is a handy way of doing large amounts of maid work in a shorter timespan. Because most of the people living or working in the mansion are maids, there are few people with more authority within the mansion than Sakuya.
Cute cosplay by Lenfried! It looks like another photo from Comiket 2010. Then again, I’m not really sure which year this is! Thanks to Yani for sending this in!