Swing for the fences

I couldn't believe I was absentmindedly bouncing Amy's bare boobs up and down and watching them jiggle, as my sister's hand ran up and down over my clothed bulge. She carried on with her homework one handed, looking annoyed but determined. "Get it together, girl," she whispered to herself. "Come on, this isn't that hard." The only way this could be better is if she were bigger, I mused idly.

'Could I?' I thought with a start. I'd never seen that in any videos, but sometimes it came up in stories. Well, porn movies didn't have much by way effect budgets. I had already made cum vanish into thin air, I had to know if it was possible. “Your boobs should be bigger,” I said, struggling to keep my voice steady.

“Tell me when,” she replied in a detached, disinterested tone, not even glancing my way. I felt her breasts swelling in my hands, first a gentle pressure against them, then pushing inexorably outward. I watched them grow, apples becoming oranges, feeling the flesh contained in my hands increase. Amy shifted slightly in her seat trying to get comfortable, gradually leaning further back as her chest pressed outwards, turning slightly so the one arm still typing wouldn't press into her ever-increasing sideboob. They went from oranges to small melons, filling then overflowing my grasp like soft, warm pillows. I couldn’t help but grin maniacally as her body did the impossible just because I asked.

“Stop,” I said finally, and I imagined I actual felt them jerk to a stop, my hands now resting atop two massive, perfect mounds, each nearly the size of her head. They were enormous, round, full, heavy, and so big that they I was certain they would threaten to hit her in the head if she were to jump too hard. I fondled them, feeling their new heft, watching their new bounce, lightly hitting the so I could watch then jiggle like jello, savoring the way they felt, before I backed off so I could take in the full sight of them.

I pulled her hand off of my clothed dick, and watched her work for a bit just so I could gaze at the gentle jiggle, trying not to laugh as her new bosom got in her way. I couldn't believe how much watching her body change turned me on.

My cock was so hard it felt like it might explode in my pants if I didn’t do something about it soon; I couldn't hold back any longer. I pulled Amy’s chair out from under her, one hand on her the small of back to keep her in place. She kept on obliviously working as she automatically stood, bending over, legs straight and slightly spread, her hips making a near 90 degree angle, massive breasts hanging down like ripe fruit, and her skirt-covered ass presented to me. I noticed that despite the overall awkwardness of her position, it seemed to have gotten her new breasts out of her way, and could swear she was working faster than before.

I ran my hands over her skirted ass, then pulled the skirt up, the thin fabric of her panties stretched over her lower lips and presenting her ass to me like two pale scoops of ice cream waiting to be devoured. I then I pulled her panties aside. Her pussy dripping wet despite her lack of outward response to anything I had done. I groaned as I ran my cock along her wet slit, feeling the heat of her pussy against my shaft, then line up to her entrance and pushed forward slowly, thrusting into her in one long, smooth motion, filling her completely with my cock.

Her pussy clenched around me as I started to fuck her, grabbing her hips, my balls slapping against her clit with every thrust, her ass jiggling with every impact. No matter how hard I thrust, her attention remained entirely on her work, even as her new boobs swung wildly forwards and back. She moaned softly, her pussy massaging my dick as it slid in and out of her, but it was more of a reflex than anything else, her body reacting to the pleasure without her mind even registering what was happening. Seeing her like that, mind unconcerned but body shaking with unregistered pleasure, I let out a primal groan, buried myself deep inside her and came, shooting hot, thick spurts deep into her pussy. Amy's entire body arched, spasming, and I felt her pussy clamped down on me as she moaned sensually, her typing actually stopping for a second before gradually resuming as if nothing was happening. I pulled out slowly, and I saw my cum drip out of her.

"Do you want me to have your baby?" she asked in the same detached tone she’d used earlier, not even glancing my way.

"If I wanted you to have a baby, I would say so," I said, her question for a second breaking the spell her indifferent sexiness had cast on me. She didn't reply, but suddenly both her pussy and my cock were completely clean, as if I’d never cum inside her at all.

I sat down on her bed, tucking my dick away, breathing heavily. Amy nonchalantly grabbed her chair and sat down without a word, her massive breasts swaying slightly. I saw her closing the file, and she stretched, hands together over her head, chest thrust out, boobs standing proudly, as she bent side to side, then stood up. She didn’t look at me or acknowledge me in any way, simply throwing herself on the bed and grabbing her phone, her new boobs a giant cushion beneath her. I sat there for a moment, watching her scroll on her phone, completely oblivious to what had just gone on. As I saw her there, laying on her enhanced boobs, a thought suddenly hit me, and I ran out of the room.

(I can't get this horizontal divider to go away!)