For a minute or two Alexa would swim by him just so and flick the end of her tail against some part of his body that was underwater. Then, as she swam by once, she moved her tail to brush up against his manhood. Then as he would most evidently would react to her touch by going to the area she just touched, she popped out of the water behind him and wrapped her arms around him saying in a playful tone "I caught you..."