Finally! He smiled in triumph as she bolted forward, bolted of course being a relative term. Had she been an otherwise normal human it would have been extremely impressive, but neither of the people on the roof were anything remotely close to normal. They were so far from normal, in fact, that 40 mph was merely a brisk walk compared to what he guessed her top speed was. And what he knew his to be. Unless he completely missed his guess, she was still holding back. Poking at his defenses to find out what he was really capable of. Unfortunately for that tactic, she already knew he was fast, and that's all he would need to turn her attack to his own advantage.
Stepping forward and to his left, and keeping his right foot where it was, he widened his stance and crouched lower, dropping his head below the level of the strike. He didn't stop there though, and extended the staff as he gripped the base with his right hand, using it as a pivot to send the far end driving toward the right side of the girl's ribcage with enough force to crack bone and create an electrical jolt strong enough to give her heart and lungs a moment's pause.