So how did Misaki knows about Touma's right hand? Even Misaka didn't know about it till she hits him a couple of times with lightning and I don't think anyone but Aleister's circle of friends knows about his ability.
Hmm Misaki knows Touma's family name without him introducing himself and there's no way Misaka would call him anything but "idiot". So does she have a telepathic power that reads mind or something? But even then, Touma should cancel her skill right.