The split-second hesitation was enough for the attack to land. Had you reacted, rather than thought, things might have been different, but...

She crumples under the blow - clearly out of the fight and possibly mortally wounded. Her cry of anguish is enough to seriously distract the remaining girls, and the monsters press the advantage, culminating in a quick defeat for the forces of light.

With the girls down or worse, there's nothing between you and the monsters. The last thing you see is a frozen fist swinging toward you - and then you know no more ...

... ever.