While Puella Magi Madoka Magica is not a yuri anime, the ero cosplayers Lenfried and Tsukushi have surely made it so, by cosplaying as Kaname Madoka and Akemi Homura from the popular series. They sure seem to love each other, with desiring look in their eyes and Tsukushi simply can't resist and starts touching Lenfried, who isn't wearing any pantsu, giving herself in and enjoying being grabbed around her ass and crotch.
Lenfried is one of the best cosplayers out there and a popular idol. She can be easily crowned as the queen of ero cosplay, as her cosplays are usually very revealing, while still looking innocent and cute. Though cosplaying various series, it would seem that Touhou is her favorite one.