Wrapping around the staff would have the same effect as that description at the point in time of Evvie turning to fire upon it. It's only that if it wraps around it would keep circling around the staff, so once it reaches the 90 degree turn is when you'd either see it start to turn around the staff again or, if you water has indeed turned solid, just stay at that position (the "embedded into her poor spine if she didn't have time to dodge" position).