Urahara Kisuke

"Found you," Kisuke calls, sing-song - not much differently than a child on a playground - before twisting in the dirt and grass in his bare feet to swing with his opposite arm, a fist this time, thrown with normal human force but jack-hammer fast and precise. There's no reason not to keep this up for as long as Dean allows it, or can manage, or until Kisuke grows bored, at any rate. Although the first blow was the one that truly mattered, building endurance would never be a bad idea, nor would practice, now and again.

"Did you feel it?" he asks. "The way your heart skipped a beat?"