You don't feel like spending who knows how long trapped alone in this pool. Thinking quickly you kick your tail has hard as you can, propelling yourself to the edge of the pool and lunging out after the former mermaid.
You just barely manage to catch her ankle, knocking her to the ground. She struggles to pull herself from your grasp but you have tight grip on her ankle. Slowly you drag the both of you backwards toward the water. At last you tumble into the water, pulling her after you and creating a big splash.