Effie was shocked at first, but gradually got over the surprise once she was in the water. She had a brief moment where she considered surfacing and scolding Leon for his dirty trick, but another idea struck her almost instantly. Smirking to herself, she focused her mind for a moment, not surprised that it took less than a few seconds for her body to comply. Being in the water made her feel energized and at home, even if it was a pool and not the ocean, so Effie needed no push to shift into her natural form. If Leo wanted to play dirty, two could play that game.
Being one of those lucky mermaids who didn't have to worry about their top parts being openly on display thanks to the beautiful swirling pattern that covered her and melded into her shimmering tail, Effie had no embarrassment as she swam underneath the water towards where she could see her boyfriend's shape. She made sure to swim carefully so he would not notice her approach at first, until she was close enough to launch herself out of the water in a graceful dive, catching Leo by the torso and pulling him back under with her.