Obito... there was a familiar name, one he would have to check his cards for, later. Madara was of course Uchiha Madara, who was dead -- so the other was delirious, and had thought this 'Obito' was the former leader of the Uchiha clan.

"Genjutsu?" There's no hiding the almost indulgent tone in his voice as Kabuto gently threads Chakra through the other's skin, bringing his other hand up to at once temporarily numb the area around his eyes and test the extent of the damage to the ocular nerves. "Oh I'm afraid you shan't be doing any more of that, Uchiha-san."