She stopped midway to her objective and asked him.
"What is it?"
"It is your turn now."
"Oh... it's ok, you don't need to worry about that."
"Of course I should. It would be very cruel to leave you like that. I would never do that."
"I-I'm not very clean, after a whole day at school, you know?"
"You think I was clean?"
"It's different, you're a boy!"
"Do you still have delusions about boys at your age? I guess it's time to show you that boys can be as dirty as girls. What do you think?"
He gave her a perverted smile and she gulped loudly, her eyes flashing with lust.
"Well... ok, then. P-please."
She started to remove her clothes and Benjamin helped her. When she was in her underwear, she took care of removing her bra while he took off her very wet panties. His removing her panties seemed to excite her a bit because she intensively watched him do so, breathing heavily. Finally, she was nude and Benjamin took a few seconds to admire her body. She was neither slim nor fat, with a normal body line. Her breasts were also the same, not too big or too small, forming a nice shape with her nipples perking due to her excitation. Down there, she was a bit hairy but not too much, her pink vagina forming a nice slit, with medium-sized lips and a visible clitoris. Of course, her juices were flooding down, drooping on the floor, the whole thing giving off an enticing smell.
"You're so beautiful, Nova."
"Really?"
"Of course."
He caressed her breast and her belly, lovingly.
"It's like a dream come true to see you like this."
"You're exaggerating, but, thank you."
Contrarily to her calm words, she looked delighted.
"I will start now, tell me if I do anything which you don't like, okay?"
"Y-yes."
She was now terribly horny and she looked like she could barely wait for him to start anymore. He didn't delay any further and put his head right in front of her crotch, took his tongue out, and gave her a long lick, from the bottom of her pussy to the top. She didn't taste dirty, contrary to what she proclaimed, just a mix of juices and some sweat from the day. She had always emphasized cleanness, after all. He enjoyed her taste fully, which, combined with her smell, was very erotic.
"Mhmm. Ben..."
She let out a long moan, happy to be getting her brother's attention on her most intimate place, at long last. He decided to handle this the same way she did for him, taking it slow, just like she gave him a long and steady blowjob. He gave her several more long licks, making her sigh in pleasure before focusing on her hole, inserting his tongue inside and lapping her vagina creases, twisting it in all directions to stir her interior as best as he could. Her breathing accelerated when he went inside her, and, after a minute of him stimulating it, she put her hands on his head and gripped him a little before twitching suddenly, orgasming on his tongue, her juices flooding his mouth and letting out a loud shout. Benjamin waited for her climax to finish, giving her a little tongue here and there to help her achieve a better orgasm, before resuming his previous cunnilingus, as if nothing had happened. Nova didn't let him, though, and, as soon as she was back from her high, she pushed him away from her cunt, blushing in shame of cumming less than two minutes after he started.
"Ugh, sorry, Ben. It was so good that I came so quickly. I-I'm not such a quick shot normally."
"I am not sure what you mean but one thing for sure, it was incredibly hot."
It seemed him feigning ignorance reassured her, as she relaxed a bit.
"R-really? Well, anyway, thank you, it was amazing."
"You're welcome."
He then went back to her pussy, licking it once again, as if this was totally normal.
"Mhmm! Wait, what are you doing?"
He stopped and answered her.
"What do you mean, what? I am just continuing."
"I came already, that's good enough."
"Ahah, do you think I don't know anything about girls when I am living with six of them? You girls are different from boys and one climax is nowhere close enough to have released all your pent-up excitation, right? Don't worry, I will take care of you until the end."
He used the same sentence she had used before, smiling cheekily. She blushed once more but didn't deny his words, only protesting weakly.
"That would be a bit unfair to you, though."
"As you said before, anything for my beloved Nova."
"Ben..."
She didn't say anything anymore so he just went back into her groin. He gave her some more licks, before focusing on her clitoris, slowly twirling his tongue around it, sometimes sucking it, sometimes simply passing his tongue on top of it. She enjoyed it very much, her legs trembling like a baby deer, probably due to her still standing while receiving so much stimulation. Fearing that she might fall, he stopped for a second, gathered their clothes together in one place, and told her, showing the pile.
"Sit here, Nova. It will be more conformable for you."
She nodded gratefully and sat on the heap of clothes, relieved to not have to stand anymore. Benjamin spread her legs and went down on her again, also happy with the new position. This time he added some fingers to his ministrations, slowly stirring her insides as his tongue focused on her clitoris. As he had decided, he never went too fast, simply going deep and steady. Nova was starting to be vocal, expressing her pleasure more and more loudly. His calm cunnilingus didn't stop Nova from soon having another orgasm, the combination of his fingers and tongue pushing her to the edge.
"You're so good, Ben, so good! You're making your big sister come again! I'm coming, comiiing!"
Her pussy trembled in ecstasy once again, releasing a wave of juices on his fingers. This time he didn't stop himself or slow down, just continuing licking and fingering as if nothing had happened. Nova was surprised by his steadiness but was under too much pleasure to protest. Soon enough, she reached one more climax, making her completely switch to focus on her sensations, closing her eyes and falling on the clothes, now fully lying down.
Benjamin went on like that for several tens of minutes, making her cum many times, until he remembered that he still needed to prepare dinner. He lifted himself from her crotch and checked his sister's condition. Her face had a blush to it from all the orgasms and she was twitching by herself from time to time, her pussy contracting and releasing juices. She was breathing heavily, her gaze a bit out of focus. He waited for a minute before asking her, worried.
"Are you alright, Nova? Did I go too far?"
She slowly turned her head to look at him, before answering, with a large smile.
"Not at all. It just felt so great that I am a bit out of strength. Give me a minute and I will be good."
She then laughed by herself and continued.
"Now that I know how good it feels, I kind of regret all the time I lost being so insecure."