He didn't attack.  But when she looked she'd see that the sword had become a living bolt of lightning.  "There aren't many lightning-based zanpaktous in Soul Society," Zhou said, flicking it back and forth.  The thing had a humming sound, the scent of ozone in the air as he it moved.  "They're quite difficult to control, too.  Sky Dragon here can be nasty when he wants to be.  You'll get to see why."  With that the hand holding the blade flicked forward, and it extended, moving fast as many shinigami with shunpo directly at her.