Every person they touched would get hurt (maybe die?)

If touched in hyper-speed. No matter how lightly touched, speed and acceleration of a hand would obliterate a person if it contacts them so fast that it's invisible. Imagine getting a low-five. The "harder" someone does it, the more it hurts. Really though, it isn't "harder" just "faster". Moving in hyper speed for an extended period of time means they are accelerating constantly until they turn off the hyper-speed, so they are essentially a walking bullet of a person.