Ty felt overwhelmed by an intense submissiveness as June pushed her to the floor and got atop her. The sight of his huge, thick penis, precum oozing from the tip, between her soft breasts, her nipples stiff with anticipation, not to mention how she felt his testicles against her crotch and imagined his sperm aching for release into her fertile body, made the reversal of their sexes undeniable. He had become male, she had become female, and their bodies ached to mate.
June moved his cock down to Ty's crotch, rubbing the tip over her clit again and then against her soaked lips, and thrust his hips into hers. He groaned and Ty whimpered as his shaft spread her open and pushed inside her. His hands gripped hers firmly and he held still, to her relief. His body felt so large and overpowering against hers, and she felt a shameful pleasure at it.
June grinned and leaned in to whisper in her ear, "You're going to be made pregnant with my child. It's inevitable now." Ty knew he was right- she couldn't have fought him off, even if she'd wished to, without her power, and she had no intention of using it. But to her surprise, her unrelenting lover actually made a sweet comment. "I'm glad the first person I get to mate with this handsome body is you."
Ty blushed hard at this, and June sat up and smirked slyly at her- then his hips pulled back and pistoned back into Ty hard, and she moaned loudly in surprise as his balls pressed against her crotch and his cock rubbed along her G spot. She expected him to continue thrusting, but instead he held still for what felt like an uncomfortably long time.
"M-mate me," she whined shamelessly, and to her relief, June pushed her into a mating press and began thrusting in and out of her rapidly. His manhood continuously hit the sweet spots deep inside her and his balls slapped her crotch with every thrust, his motions gathering speed and her moans growing in volume as he went.
Ty felt more and more overwhelmed with pleasure as June bought her steadily toward her, and his own, climax. The people they had been before Ty wished for the virus felt totally detached from who they were now, and they felt focused only on the pleasure of mating. At some point, June's hands had moved from holding Ty down to cupping her breasts, which further heightened her pleasure.
While Ty whimpered and moaned inarticulately, June managed to sneak in some dirty talk through the fucking. "Such a good girl," Ty heard, "Breedable slut," "Get pregnant with my seed." His focus on using Ty to reproduce only heightened her pleasure, reminding her of how they'd changed.
At last, one of June's thrusts against Ty's sweet spot pushed her over the edge, and she gasped and whimpered in satisfaction as she came around him. And she saw in her mind's eye how her clenching tightly around June's cock made him peak, his ejaculate splurting from his cock head and flowing into her depths.
She saw his semen reach inside her, and how his countless sperm swam eagerly through her, amazed at how weird it felt to have a man's seed mating her when she'd only been able to get bred by them, and June had only been able to produce them, for a few minutes. Soon they found what they sought- an egg nestled in her ovary- and ate away at its walls.
Once one of them fertilized the egg, it moved down to settle in Ty's womb, soon implanting and impregnating her. Ty felt an indescribable emotion at realizing June had bred her as he said he would, but knew she loved it.