Bon Bon wouldn't admit it, but she was worried, besides the obvious reason for being so. Director Mouser was a known figure, and could be reliably counted on to follow the habits the Shades were instilled with from their inception. Rose changed that. She was an unknown quantity, and at this point Bon Bon couldn't tell if her demeanour was an act to hide the intelligent pony beneath, or was actually who she was, and she'd gotten the position as Head of the Shades by other means. Either way it made her unpredictable.