Funny how there's no Sherlock Shellingford tag (from Tantei Opera Milky Holmes), as it's who Himawari is cosplaying as (and Sakurako is commenting on, since Sherlock is as flat as a board, but Arsene/Henriette however...). Oh well, tag edit...
Ah, also Himawari is cosplaying as Ryuushi/Ryuuko from Denpa Onna... Unfortunately I'm not as familiar with that series, so could someone else do the honors?