The gunfire is not meant to harm, once it's evident that she has a level of invulnerability. More to distract, affect the senses... and aid her opponent in vanishing into the shadows and dusty debris caused by their crashing through the floors.

With the quickness of a jungle cat, agumented by the speed of the inhuman vampire he most likely is, three bounds later, he's using her charge against her, trying to leap on her back and jab that energy dagger right into her eye...