"Show me your tits, sis."

"Yeah, that figures," she replied with a knowing grin, letting her skirt fall back down.

"Wait, he did all that and you still have your bra on?" Jenny asked.

"I still have my shirt on," Amy countered. "He went right for the panties after groping me through my shirt."

"Really?" Jenny commented in surprise. "Then again, somehow he managed months past his eighteenth birthday and before using someone. I expected him to grab someone at his party. I even wore crappy clothes to your house for months in case he wanted rip them off to use me."

I didn't have time to process that before Amy stood up next to the bed and pulled her t-shirt off. Her bra clad breasts bounced right before my eyes, before she reached behind to unhook her bra. I groaned involuntarily as her boobs spilled out, and my sister smiled cutely as she threw her bra on the bed. Her large tits swayed as she sat back down. Before she could resume talking with Jenny, I grabbed her bare boobs, squeezing them experimentally, making my sister groan.

"Mauling my boobs," she managed to gasp out. I leaned in and buried my face in her cleavage, drawing an even louder moan. I continued this for a bit, my sister too into it to remember to narrate for Jenny.

"What's he up to now?" our audience asked impatiently.

"John's motorboating me," my sister replied.

"Fuck, I know how big your tits are," Jenny replied. "I don't suppose you could snap me a pic?" she asked. "Some visuals would help me enjoy you using your sister. Imagination is hot and all, but..."

"I think he likes that idea," Amy commented as I kneaded her more forcefully. She reached past me, careful not to dislodge my face from her chest, and grabbed the phone. She pointed it straight down into her cleavage from above, and I looked up, face sandwiched between her breasts, and smiled at the camera as she snapped the picture and sent it.

"Wow, that's hot," Jenny said. "Just all up there in them big titties. He's making good use of your assets," she added glibbley. "Did you want me to play with mine too, John?" she asked. I froze for a second, then grunted in affirmation as I grabbed my sister's nipples, tweaking them lightly, moving in to suck on one, making her groan.

"Damn, now he's sucking on my nipple," Amy said breathily. She grabbed my head and pressed me into her firmly. "Like that, bro. Use my tits like that." I couldn't believe how lucky I was to be able to do this to her. She gasped when I lightly bit a nipple, tweaking the other one as I did. Without letting it out of my mouth, I looked up to make sure I wasn't hurting her. She smiled down at me and I sucked hard as I heard a bit more rustling over the line.

"Done?" she asked when I let released her nip from my mouth.

"Yeah," I replied, then moved upwards and kissing her as I kneaded them. I groaned into her mouth she kissed me back, her tongue pressing against my lips. I was a novice at this too, but she didn't seem to mind.

"What is going on?" I heard Jenny say. "What's that sound?"

I broke the kiss and said, "Just making out with Amy."

"Please let me video chat with you. I can't stand waiting for you to tell me what's happening.," she pleaded. The line buzzed, and Amy, after I give her a quick nod, activated the video chat and held her phone up as I kissed her. "Fuck yeah, that's what I am talking about," Jenny said, and Amy moaned into my mouth in response. I slid my hands over my sister's body, along her sides and then back to her breasts, kneading them as we made out, putting on a show for Jenny.

"So hot," purred Jenny when I finally pulled away, still fondling my sister's boobs. "Is he as good at kissing as he is at eating you?"

"Fucking natural," Amy replied. "I want to be annoyed at him for not using me sooner, but it feels too good right now."

"Not fair! Jenny can see us, but we can't see her," I commented jokingly to Amy, before kissing her again. Amy moved the phone so I could look at it, but it was just a view of the ceiling. Jenny's phone shook for a second, giving a closeup of her hand and then the spines of few books, and then she propped it up and sat back down. My eyes boggled as I realized Jenny had her shirt up around her shoulders, bra open and hanging off her arms, boobs bare as she played with them with one hand, the other down her unzipped pants, while behind her another girl, who must be her roommate, quietly worked on something without reacting to what was going on behind her.

"Fuck, you didn't say your roommate was there!" I said in shock, breaking the kiss.

"You never asked. Why does it matter?" Jenny replied. "Oh did you want Debbi to enjoy you using Amy too?" she asked, beginning to turn around...