The red and black threw people off cause those are High-king colors, but since we've precluded all the legal members of that group, which other groups wore red and black?
Well, Ongaku Gatas did, but that one was all sequins and no black border.
Red and black featured in Naichau Kamo, but those were leather jackets.
But then again, the lighting seems a little too soft for a stage pic. Maybe I'm barking up the wrong tree, thinking it was from an H!P concert, where the girls sit down.
What she's sitting on seems cushion-like as well... hmmm.
In short, I have no clue right now.