Ty watched Aiden awkwardly step into the bathroom to pass the towel, a visible bulge tenting the front of his pants.
Lifting her arms up, she turned to let him wrap the towel around her. He cupped her breasts through the towel, pushing his luck.
"Aiden, is it? You're pretty bold, has anyone told you?" Ty giggled, and she pressed her butt against his crotch, making him shudder. His hard-on throbbed in anticipation through the fabric. Aiden groped her breasts more firmly, his breath weavering. They were a fully grown woman's breasts, larger than any teen's he had touched before.
"I'm... I'm not a little boy," Aiden said in a voice he hoped sounded masculine and confident, though his hands were trembling. A wetspot formed in his underwear as he was dry humping Dustin's big sis.
"Show me then", Ty commanded, arching her back to tease Aiden further.
He immediately began unbuckling his pants, letting it and his underwear fall to his feet as he pressed his erection behind Ty, pushing her forward. She stumbled to the sink as he followed close behind; the towel dropped on the floor. Aiden still behind her, she guided his length between her legs and to her pussy to welcome him. After poking around for a second, he finally got the right angle and his cock rammed into her from behind, making them both moan.
"You're on the pill right?" Aiden panted in her ear.
"Just breed me now, or do you want my brother to find you're fucking his sister in his own home?" Ty ordered him impatiently.
Aiden picked up the pace immediately. She could tell he lacked experienced and wouldn't last long. His emotions were getting the best of him. As she was gripping the edges of the sink and looking at herself in the mirror, her heavy breasts jiggling in rhythm with his slamming, she could see him behind her. He was sweating and grunting louder, his cock hardening even more inside of her; he was close.
"I'm gonna... I'm..." he squealed miserably as his load escaped him already, exploding into Ty's womb. She was so focused on her own pleasure that she barely registered his seed fertilizing one of her eggs. She didn't want it to end just yet. The pleasure emanating from her insides was obscuring the sensation of the fetus growing alongside the other two.
"Don't... stop", she growled under her breath. She pictured his spasming cock in her mind's eye: far from softening, hardening even, ballsack swelling... Cumming again.
Moaning in exstasy, his legs trembling, Aiden's hips bucked wildly as he felt another orgasm build inside him. "Ooh fuck, it's... I'm..." he tried to speak as his balls drew close to his body again to empty themselves.
Ty braced herself against the sink to welcome the massive load, her womb instictively releasing another set of eggs. Aiden let out a lewd cry - too effeminate for his looks - as he hit a second climax. Cum gushed through his swollen cock and overflowed Ty's womb in successive waves, excess fluids dripping out.
She felt him impregnate her a second time, her own body on the verge of climax. Almost there... Without a second thought, she willed the teenager to come inside her a third time, and he hugged her adult body tightly from behind, shaking as pleasure overcame him again. A third and last heavy cumshot erupted from his spasming cock.
Ty finally came as his seed filled her completely, more spilling out; her body rocked with pleasure and her high pitched moan echoed in the bathroom. The mirror revealed to her a slightly bloated belly, the third and last fertilized egg she had released developping into a grape-sized fetus like the previous ones.
Aiden disengaged from her pussy and fell to his knees, panting. His rock-hard, swollen, almost painful cock throbbed in front of his eyes, cum still oozing out. Fluids splattered on the bathroom tiles and his underwear and, self-conscious, he pulled on his pants to try and barely cover himself.
"S-sorry this isn't... I'm... I don't usually cum so much," Aiden tried to articulate, out of breath.
Ty wrapped the towel around her with a grin.
"I won't tell... if you keep this a secret as well," she said, "and you'd better hurry if you don't want to get caught by my brother, I think he's right at the frontdoor".
She giggled and left him scramble to wipe the splatter of cum off the floor, his ass still out of his pants. Closing the door of her bedroom behind her, she removed the towel and wiped the excess cum off her body. She was on a cloud, her womb full, whole body still tingling.
Looking down at her belly, it did look a little bloated, but it wasn't too bad, she thought. She noticed her shredded dress on the floor from her previous session of experimentation, and sighed. She was a bit exhausted after all this action, perhaps.
Laying down on her bed still naked, she decided to take a nap for the rest of the afternoon, absentmindedly caressing the small curve of her belly as her thoughts drifted towards Eileen again, dozing off.