When his tennis match was over, Alan rushed directly to Kim's house. He hadn't showered after playing, but he figured he could shower there. His low-energy problem was the same as always, so he really wanted to nap, but he figured he could work in an hour or two of sex and then take a late nap at home before dinner. That's exactly what he ended up doing.
Alan showed up at Kim's house at 4:30 p.m. He rang the doorbell, which was answered immediately by both Kim and Katherine, who had been waiting anxiously for him to arrive. They were both wearing especially sexy, revealing outfits just for him. However, he was so tired from the tennis, plus biking to Kim's house in a hurry, that he couldn't really appreciate it. He just smiled and said, "Hey, you two look great! Kim, could I take a quick shower? Maybe that'll revive me."
Of course Kim didn't object, so a minute later Alan was naked with the shower water running over his body.
The girls gave him a few minutes to get clean and hopefully somewhat revived. Then they surprised him by joining him in the shower.
He didn't have it in him to object, especially once he got a good look at their naked bodies. He said, "Oh, man. I can't believe this is happening. Girls, I warn you; it'll be a tight squeeze in here."
Katherine replied, "That's what we're hoping!" She giggled at the double meaning.
He shook his head. "Duh. I really walked into that one, didn't I? Kim, what are you doing?"
He asked that because Kim had wasted no time, kneeling before him in a flash. In fact, by the time he finished asking her what she was doing, she was already licking his penis. Unfortunately, it was flaccid, but that didn't discourage her at all. She did focus more on licking his balls though, massaging his perineum with her tongue until the proximate stimulation of his prostate made his penis grow erect.
Then Katherine moved in. She managed to kiss his lips without getting in the way of Kim's efforts. Between happy smooches he asked his sister, "So what's this all about?"
Katherine replied as she licked his neck, "This is called number-one-fuck-toy service! Kim has agreed to be assistant fuck toy for the day. So feel free to do anything to me, to us, that you want! Anything at all!" After some more kissing, she added, "In certain other places, we have to be careful about what we do. But here and now there are no rules at all!"
"I like the sound of that!" he exclaimed with genuine excitement. The girls were doing a good job of reviving him both mentally and physically.
Despite the "anything goes" situation, Alan was content to just let Kim suck him off while Katherine kissed him. He still wasn't all the way back, and his muscles were aching from all the tennis. Just standing there with his back against the wall, intimately kissing his sister while the water massaged his sore muscles, felt very nice. The fact that Kim was blowing him at the same time was a very big bonus.
They kept at it until he was on the verge of a climax. Then they got dry and moved to Kim's bedroom.
Alan was in a mellow mood. He wanted to fuck for a while, but in a way that wouldn't take too much energy. He told Kim and Katherine while he sat naked on Kim's bed, drying his head with a towel, "I've been reading some books on sex techniques, but last time I was too excited to use what I'd just learned. Now I want to try this stuff out. There's a book that goes on about how awesome tender, slow, love making can be. So that's what I'd like to try. Did you know a woman is supposed to have seventeen different erogenous zones?"
"Seventeen?" Katherine asked quizzically. "That can't be right." She and Kim sat side by side next to him, naked, eagerly waiting to see whom he'd choose to fuck first.
Alan pointed his finger at Katherine and tossed the towel aside. "Kim, hope you don't mind, but I think I'll start with some sister fucking."
No one was too surprised by that. Katherine immediately hopped up on the bed and lay down.
Alan resumed his train of thought about erogenous zones even as he smiled and pressed himself down onto his sister. "Seventeen zones, Sis. Seventeen."
"No way!"
"Yeah, way." He pushed his cock straight in. "You're going to find out. There's the back of the knees, the earlobes, the armpits..."
"Armpits? No way, Big Rig Brother. There's nothing sexy about that. ... Oh, God, it's so full! My poor cunt just ... can't take it. ... Push! Harder!"
"That's what the book says, Shaved Little Sister. Let's check it out. But I can't do two women at once. Let me show Sis first, then I'll show you, Kim. Then, once I get the hang of it, I can get some help from one of you, like I'm Santa and I've got a sex elf."
Kim laughed. "I could have guessed who gets the seventeen-zone treatment first, but that's okay. I'm happy to be a sex elf, if that helps. Looks like you're getting into the Christmas spirit early."
Alan smiled at that while he started to find his fuck rhythm. "Yeah, they say Christmas starts after Halloween these days. Let's do just a little bit of this in and out and then move to some slower stuff. Bouncy Little Sister, I like how Kim has you all lubed up with cunt cum and then some before I even start."
"Oh, I am. I'm so fucking ready!" Katherine panted. "Spear me! Fuck with it! Fuck! Fast fuck! Fast fuck! Hit me with your baby juice!"
Alan's plan to take it slow and easy went down the drain as he got swept up in her enthusiasm. He gave his sister a quick, hard and intense five-minute fuck. The sound of his balls repeatedly slapping against her filled the room.
But then, just as they were both about to cum, he became completely motionless, with eyes closed. Both Kim and Katherine were puzzled by that; they began to wonder if he'd passed out. But after a minute he re-opened his eyes and resumed his rutting, though now in a completely different manner. He settled in for a relaxed, "tender love" fuck, which was what he'd wanted to do all along.
Kim was content to watch and masturbate. She was realistic enough to recognize that she wasn't as beautiful as Katherine, nor could she ever compete with their incest taboo and close sibling bond.
With the slower fucking, Alan had time to try out his book learning about the seventeen erogenous zones.
Sure enough, Katherine discovered erogenous zones that she hadn't even known existed, like the soles of her feet. She really got into having her toes sucked. She also had a sensitive neck and ears.
Alan made a mental note to focus on her toes a lot more in the future. Then, during a strategic break to give his dick a second wind, he put his fingers in her slit and played around inside.
Even though she was somewhat sore from their just-concluded fuck, she wanted more. "Oooh! Yeah, just like that! Kim, I am in the zone!"
Kim asked, "What zone?"
"You know, 'The Zone'. The blissful state where everything is absolutely perfect. 'Cos my big brother is fucking me and loving me, and doing a damn good job of it!"
He modestly shifted the topic. "Speaking of zones, let's not forget the best spot of all. Your G-spot. Right here." He knew it pretty well on his sister from previous sessions, so he had no trouble locating it this time. "I'm gonna get to know this spot so well, I'm gonna be a god-damned G-spot-ologist."
She purred and moaned. She really was in seventh heaven.
As they played with each other, Alan spoke his mind freely. "Little Sis, I have to be honest. I really think you are the best-looking girl in school." Suddenly he remembered that Kim was in the room, masturbating just a few feet away from them. He belatedly added, "No offense, Kim."
Kim responded, "None taken. At least I have the looks to get on the cheerleading squad, so I know I'm not chopped liver. But then there are the drop-dead gorgeous types. And I'd agree that she at least ties with that group, in a tall, willowy sort of way. When you get to the looks of like Heather, Christine, Amy, Donna, and Katherine, it becomes impossible to pick a best." (The Donna she referred to was Donna Giovanni, Heather's main rival in school, who was also well-known for her beauty.)
Alan was relieved that Kim didn't seem offended. He tried hard not to make comparisons between the women in his life, in part because it was such a potential minefield. "See Sis? Screw Heather. I think her tits are fake, and probably half the rest of her is augmented somehow. Your body is really outstanding." He ran his hands over her breasts and down her tummy, then to her hips. "You don't have a single blemish, or hardly even a scraped knee."
He brought one hand up to cup her face while his other hand kept exploring. "And your face is so pretty. You could be a model, and I do mean a really high-paid model. How lucky am I to have such an amazing sister?"
Katherine tingled all over from the compliments and the fondling. But she pouted, "What about Christine? Isn't she the most beautiful girl in school? That's what a lot of people say."
Alan realized that he had to be extremely diplomatic, because there was no denying that Christine was a total knockout and totally real. "I agree with Kim. When you get to that level of beauty, it becomes pointless to compare. All I know is that every time I see you, I want to love you, possess you, fill you up with my cum."
Katherine squirmed under him excitedly. "Oh, Brother! Me too! I love you too!" Her hands found his boner, which she stroked while trying to pull it back into her slit. "Every time I see you, I want you in me! Gaawwwd, I want you to fuck me forever! That's why I want to be your fuck toy! I really mean it. I love you so much!"
They kissed and shared their love for each other. He still needed a longer strategic break though, so he lay right next to her in a way that prevented her from fitting his erection in her cunt, or even from jacking him off much.
Then, not wanting to hurt Kim's feelings, Alan turned to her and said, "Kim, I think you're very beautiful too. And you're still growing; in another year you'll be even more of a stunner. But you have to understand that my feelings for my sister are inherently different, and very special."
Kim understood. "No problem. Believe you me, I completely agree. Your sister is hot. Your whole family is remarkably good looking, including you and of course your mother. You Plummers must have the most amazing genes."
Alan smiled a wry smile, because Kim was forgetting that both he and his sister were adopted.
Katherine finally replied, "You think you're lucky, Big Farm Silo Brother? How lucky am I to have such an amazing brother like you?" She gazed into his eyes. "I've loved you so long. I don't care if you happen to be my brother; you're the one that I love."
"I love you too, Little Sis. In fact, I'm really glad that you're my sister, because that means I'm fucking the girl I love the best. I have my own Playboy centerfold model just across the hall from my bedroom, ready to fuck any time."
"Not just ready," Katherine corrected. "I live for it! I suck on pens and pencils all day long at school, just dreaming about you filling my mouth or my cunt."
Kim laughed. "It's true. The funny thing is, she really does. Whenever I see her, I have to remind her covertly to not be so obvious about her pencil sucking."
"I stand corrected," he said, amused. "But my point is, not only are you the ultimate fuck, but you're also the kindest, most loving girl. You always made this brother very happy, way before our sex even started, just by being you."
Both of them shed a few tears of happiness even as they continued their gentle foreplay. Alan was still toying with her G-spot, which was having its intended effect.
Kim gave them their space and played with herself more or less non-stop. She ardently wished that she had a brother like Alan, after seeing how good he and Katherine were for each other.
The two siblings took another half hour to fuck the slow way, until they came together with a lot of clawing and screaming. Then there was more fondling afterward, until Alan's time at Kim's was running out.