While Ty and Eileen had satisfied their new sexes' transformed desires, the result of their fucking was still finalizing. Inside the semen Eileen had pumped into Ty, an innumerable amount of sperm his body had formed had begun to swim through Ty's passages guided by an instinctual desire they could sense would be satisfied by something deep inside her.
Soon they came upon it, finding an ovum inside Ty which her ovaries had produced in the surge of hormones when she had changed sex. The horde of strong, energetic seed eagerly chewed away at its walls, each and every one desperate to fertilize it and make it develop into life. Soon one of them made it capitulate and moved inside, guiding it to implant inside Ty's womb as it began to divide. Just minutes ago, he had been a boy; now she was a pregnant girl.
While this whole process occurred, Eileen withdrew himself from Ty, and she watched as his penis emerged, covered in gooey white male essence and sticky translucent female essence. More of his cum oozed from her freshly fucked pussy lips, the sensation of leaking very strange to her.
Slowly, as she and Eileen stared at their bodies, her awareness of her changed sex settled in in a slightly less fetishized way. She had just used her wish to castrate and emasculate himself, and he had just fucked her raw and cum inside her. There was quite a high chance he had gotten her pregnant with his child.
When Eileen carefully took her face in his hands and kissed her, she realized she kinda liked that all of that had happened.