Lisa looked down at her body, and gasped as her upper body became transparent, and water-filled, as she had asked for. As she breathed, she saw air bubbles. She didn't yet contain any fish, though. She went to Ty's mirror, and stared at her body, and tried out various poses. As she'd asked, she was able to move perfectly normally. "What about the fish?" she asked.
"Coming right up," Ty said. "I just wanted to make sure the basic transformation worked. How do you feel?"
"It feels wonderful! I feel a bit chilly, though. The temperature for the fish is below my normal body temperature. Please change me so that I feel that the temperature of my aquarium part is normal."
Ty did that, and brought into existence an assortment of fish inside her, along with the plants and gravel she wanted. He also created some rocks, a little pirate treasure chest and some tiny Roman ruins. The fish included a few each of guppies, neon tetras, bettas, angel fish, a clown loach, and a redtail catfish. "You're not big enough to hold a whole lot more fish," Ty said.
"Oh, Ty, this is wonderful!" she said, staring at herself in the mirror. "It's even better than I dreamed of!" She cupped her breasts in her hands, lifted them, and watched as that resulted in currents that shifted the fish and plants a little. Of course, her arms and hands were also part of her aquarium body, transparent and water-filled, and she saw that a few fish were in her arms. She turned away from the mirror, pressed her body against his, and kissed him. Ty found that her body still felt normal against him.
Lisa pushed him down onto his bed, climbed on top of him, and started to ride him. He thought about putting his hands on her breasts, squeezing them, but it was too fascinating to watch the fish inside her, as she moved.
"Maybe you should make some of your other bodily transformations," Ty suggested.
"Oh, no," Lisa said. "I like myself just like this." But she thought for a few seconds, then said, "Well... maybe just a few more transformations." As Ty watched, she became slightly taller, and grew second pairs of arms and breasts. "Just to give the fish a bit more room."
Ty smile, and added another pair of arms to himself, and started groping her breasts, after all.
After they came, Ty asked, "Shall we go back to normal time now, and go to school?"
"Do we have to?" Lisa playfully whined.
"No, we don't have to," Ty said. "If you want to do other things, there's no rush."
"It's just that I don't want to give up my aquarium form so soon. Oooh!" she squealed.
"What was that?"
"One of the fish keeps poking at my nipple. From the inside!"
"That fish isn't the only one," Ty said, and poked all four of her nipples with the index fingers of his four hands.
"Not fair! You can't gang up on me with the fish!"