That night, Lucas ran the experience over and over through his mind. Stroking himself, he would picture the way Elisa's lips looked wrapped around the head of his cock. The way her small, pale breasts pressed against Emily's as they shared his cum in a deep kiss. He came pretty quickly, letting it coat his hand and cock, and continued stroking. He imagined it was Ellie's hand on him. Then, he thought of the way it had felt to have both his sisters touching and exploring it.
Emily, beautiful Emily fingering herself to orgasm, her other hand buried between her twin sister's legs. Lucas came again without ever going soft, and fell asleep covered in his own cum.
As Lucas walked nervously down to breakfast, he wondered how his sisters might feel about the previous night, having had time to think about what they had done. What if they told their mom? But, they couldn't do that. Unless, they somehow blamed it on him. But, breakfast was the same as it always was. Mom would be home early that night, and the girls were sleeping over with the squad.
"Oh, Aunt Jenna has a seminar tomorrow, and needs a babysitter. She'll pay, but you have to get over there pretty early. How about it, Lucas?" His mom asked over coffee.
"I have a paper due on Monday. It's on the effects of-"
His mom held up a hand. "You lost me at paper. That's okay, I'll just go. I haven't seen her kids in months, anyway."
Lucas didn't really have a paper due, but he certainly didn't want to watch his bratty cousins all day. With his mom home all day today, he was planning to take advantage of the empty apartment tomorrow for a lot of time masturbating. That was pretty much all he wanted to do anymore. Especially after that first glimpse of his sisters.
Emily called shotgun on the way to the car. They only lived about fifteen minutes from the school, but it was usually fifteen minutes of nonstop chatter of whatever teenage girls talk about. That morning was the complete opposite, until Lucas decided to break the silence.
"Um. So. About yesterday?"
"What about it?"
"I mean, it was wrong. Brothers and sisters aren't supposed to do stuff like that." It wasn't how he really felt, but he thought he should say it.
"Stuff like what?"
"You know what."
Emily proffered a wicked little grin and said, "You mean like sliding my hands up and down your hard cock? Or how you filled Ellie's mouth with your hot, sticky cum? Or maybe it was watching us push your cum back and forth with our tongues?"
Elisa laughed from the backseat. "God, Em, you sound like a total slut."
"Yeah, well, I feel like a total slut. Seriously, Lucas, what you saw us doing before. We were just curious, and it felt pretty good. But ever since I saw your cock, I've been horny like nonstop. God, just talking about your big, beautiful dick is getting me wet." Emily giggled as she looked down at Lucas' lap. "I guess you like it when I talk like that. Did I make your cock all big and hard talking about how much I want it? Can I see it? Can I touch it?"
Her hands were already undoing his jeans and fishing out his erect cock. She wrapped her soft hand around it and began stroking. Lucas glanced over his shoulder to see that Elisa was leaning forward so she could see. She had hiked up her skirt, pulled aside her panties and was rubbing her pussy. Lucas struggled to keep his eyes on the mostly empty road.
The car swerved and Lucas pulled it straight with a gasp. Emily had lowered her head into his lap and taken half of his cock in her mouth. Her velvet tongue slid hungrily along his shaft as her lips locked down and she sucked hard. His hips rose and he felt the head of his cock hit the back of her throat. Her head jerked up as she gagged. Then, she drove her mouth back down. She began bobbing her head up and down, her hot, wet mouth filled with his throbbing cock. He hit the back of her throat over and over, and she gagged a few times, but managed to fight through it.
In the backseat, Elisa had thrust two fingers in her wet pussy. She worked them in and out as she rubbed her clit with the middle finger of her other hand. Watching her twin sister sucking their brother's cock, she started cumming with a loud moan.
"Oh god, yeah Em, suck his big cock. Ooohhhh, fuck, I'm cumming, yes, god yessss."
Hearing his sister's orgasm, Lucas began pumping cum into Emily's mouth faster than she could swallow. Cum dribbled out of her mouth back onto his cock, and she bobbed up and down, slurping it back into her mouth. When he finished cumming, she sat up, with a huge grin, lips glistening with his cum. She licked her lips, and giggled.
"That tastes so good. I didn't think it would, but when I tasted it yesterday, I knew I had to have more. Did you like it?"
"Jesus, Emily, that was the greatest thing I've ever felt."
----
Class and work that day passed in a haze. Lucas was ordinarily an excellent student, but there was simply no way for him to focus on anything but his sexy sisters. After school, he went home. He thought about going to the game, but none of his few friends would be there. Also, seeing Elisa and Emily in those little cheerleading outfits would just make him horny.