Robots Prevent Masturbation

Lucin thought about it, then shrugged and fingered his nipples some, trying not to overthink whether Celeste was actually enjoying him doing that sort of thing to himself. Probably she wasn't. It wasn't the same effect when a boy did it as when a girl did. Totally different.

Most of the time he would have been right. However, in the context of being overly horny herself, Celeste kind of enjoyed the display anyway. Which hadn't been her goal, she really did just want to test things, but a little extra sexiness might as well be enjoyed as long as it was in front of her.

"So she doesn't mind that, is the point," Celeste said, trying not to appear as though she'd been staring too hard at her brother.

"Yeah, fair enough," Lucin said. "If you can get off to nipple play, more power to you."

"That's not really what I was thinking."

"What were you thinking then?"

"I was wondering how Matilda feels about anal."

Lucin took quite a while to process the statement. His mouth opened and closed a few times as he almost said something, then thought better of it. His eyes flicked to Celeste repeatedly, drawn to her boobs, but also to the tabletop in front of her as though he could see through it.

Celeste waited patiently but with growing nervous excitement for him to catch up to her.

"Like if you put stuff in your butt?" Lucin asked.

"If either of us did," Celeste corrected.

"You think I'd do that?"

Celeste rolled her eyes. "Please don't tell me you're one of those people who thinks butt play for guys is exclusively gay."

"No! Of course it isn't. Just... I've never really done it."

"Oh really? Found something you're shy about, did I?"

"I... maybe. Whatever."

Celeste, eager to tease her brother, nevertheless reined herself in. She wanted them working as a team, after all.

"Ok so... me either, actually," Celeste admitted.

"And you were gonna tease me?"

"I know, I know. It's just instinct sometimes. Anyway... what do you think would happen?"

"I dunno. It's not really masturbating, is it?"

"Don't see why not. People can cum from it."

"Just in porn though," Lucin pointed out.

"If they can do it in porn, they can do it in real life. It's not all fakery, you know. You can see when dudes cum for real. And if a girl squirts like crazy, kind of hard to fake that, I'd think."

"Have you... watched a lot of this stuff?"

"Some. You?"

"Same, I guess. I kinda have periods of being more interested in it sometimes. Sometimes I watch a lot of butt stuff. Sometimes I don't."

"Fair." Celeste toyed with the food remaining on her plate. "So... should we try it?"

Lucin struggled with his answer. He wanted to say yes and no at the same time, and both pretty strongly. The decider for him was the near-certain knowledge that he'd get to see Celeste playing with her butt.

"I'm too horny for my own good," he said aloud.

"I think we've both known that about ourselves for a while. That's a yes then?"

"Yeah, let's try it."

"Cool." Celeste bounced to her feet. "Let's go."

"Now?"

"You mean after we've had time to think about it?"

"... you're right, let's go now."

Lucin darted from the table, followed closely by Celeste. It was, perhaps, rude to just leave their dishes on the table like that, but then Matilda had been quite rude in not letting them masturbate, so the hell with her.

"Whose room?" Lucin asked.

"Mine, I guess. I need to get a shirt."

"Why do you need a shirt?"

"Because," Celeste said as she entered her room and rifled for a top. "I'm gonna be quite exposed."

"You're already quite exposed."

"You just wanna see me naked," Celeste accused.

Lucin nodded. "I mean, yeah, obviously. Do you not want me to see you naked?"

"I... I'm not used to showing anyone my butthole."

"Oh. Yeah, I guess not, huh."

Celeste pulled on a loose shirt that came down just past her panties. When she removed her underwear, Lucin couldn't quite catch a peek of her pussy, no matter how hard he stared.

Celeste smirked at her brother's inquisitiveness, but was simultaneously bouncing with nervous excitement.

"Ready?" she asked.

"Why you asking me? You're the one doing it."

"You're gonna try it too! Don't think I'm the only one gonna play with my butthole."

"Fine. You first though."

Celeste rolled her eyes, but accepted the condition. She'd kind of expected it anyway. She wasn't sure if she could get Lucin to do butt stuff to himself period, really. Boys could be funny about things like that. Although girls could be equally weird about it, so maybe it was just people generally.

Lucin tilted his head with interest as Celeste reached behind herself. He couldn't actually see anything, but the overt implication of what she was doing was certainly intriguing all on its own.

"Are you touching it?" he asked.

Celeste nodded, slightly breathless despite a distinct lack of physical exertion. "Yeah."

"Well... seems like no reaction then."

"Certainly does. But, like, I might have to actually go inside to trigger something."

"You think? How sensitive is Matilda anyway?"

"No idea. I assume she's got some crazy senses though. I mean she can sniff out masturbation behind closed doors and everything."

"True. And she doesn't actually trigger when you're, like, using the bathroom or anything."

"Yeah. Too bad I don't have any lube to try out right now. Maybe spit?"

Lucin fought a small wave of arousal. It wasn't doing any good. He was turned on as it was, and it was only getting worse the more Celeste 'tested' her butthole.

"I've got some," he volunteered.

Celeste looked up sharply. "You do?"

"Yeah."

"I thought you didn't do butt stuff before?"

"I haven't."

"Then what's the lube for?"

Lucin stepped back under his sister's sudden, intense scrutiny. "It's, uh, you know like toys for jerking off? Like, that are supposed to be kind of like pussies or whatever?"

Celeste nodded. "Oh. Those."

"Yeah."

"Well go get the lube then. I don't want to stand her with my ass hanging out all day."

"I--"

"I know you'd enjoy it," Celeste said with a perfectly executed eye roll. "Just get the lube."

Lucin dashed off. He passed Matilda in the hall, who continued to not give a single shit about any lewd behaviours in the house, other than genital gratification. She was such a weirdo.

"Got the lube," Lucin said.

Celeste grabbed it from him and poured a little on her finger. She again reached back behind herself and rubbed her finger over her butthole.

It had never seemed necessary to play back there before. Vaginal stimulation had always been fun enough on its own. But now, without her previous options available, Celeste was kind of enjoying this new naughty touch. Fingering her little bum like this. In front of her brother and everything. It felt so dirty in a really good way.

"Is your finger in?" Lucin asked.

"Mmhm."

"Well Matilda was just down the hall, and she clearly isn't minding this."

"It seems not," Celeste said faintly.

"... how's it feel?"

"You should try it."

"I will. Just... what's it like?"

Celeste snorted. "What do you think it's like? It's like a finger up the bum."

"Yeah but... do you think you could masturbate like that?"

"I don't know. I mean, it feels kinda nice. And weird. But, like, I honestly don't know if I could cum from having things up my butt."

"Only one way to find out."

Celeste grinned. "True. You try it now."

Lucin swallowed, then nodded. He had to do it or he'd be taunted mercilessly. And really, he privately was kind of happy to have pressure to try it. He didn't know if he would on his own.

Lucin pulled off his pyjama bottoms, leaving himself naked, not even the protection of a shirt like Celeste had. He didn't mind. He was horny, and the way his sister stared at him was a thrill he was really getting to appreciate lately. He still thought she was more fun to look at naked than he was, but he was biased.

"Damn you're hard," Celeste said without meaning to speak aloud.

"Well yeah."

"So much precum...."

Lucin blushed. "Shush. We're supposed to be experimenting here. Take it seriously."

"I am. You just got naked. What do you want from me?"

"I...."

"I'm way too horny. You shouldn't be so fascinating to me."

"Same," Lucin said.

The sibs blushed and tried to determine where they should look, then just gave up and checked each other out more.

"Do it now," Celeste urged.

Lucin nodded and took some lube on his fingers. He leaned one hand on Celeste's bed while reaching back with the other. He was aware that Celeste was now getting a much better view than he was, and tried to feign nonchalance about it even while his cock pulsed and spurted more precum.

Celeste still had a finger up her bum, but used her free hand to spread Lucin's butt cheeks and get a better look as the tip of his finger disappeared.

"Hey!" he protested.

"Just looking," Celeste said absently. "Definitely seems like we can get away with this."

"Yeah, it does. You don't have to look quite so close though."

"Don't know that I can help myself."

Celeste, way too horny for her own good, kept right on staring until Lucin got embarrassed enough to pull his finger back out of his ass. Slowly, robotically, but with great sense of purpose, Celeste pulled her finger out of her butt too, then pressed it against her brother's tight, slippery little hole.

Neither spoke. Neither had the slightest idea what to say. Their parents would have been amused to find them so speechless, if not for the rest of the circumstances.

Celeste's finger slipped inside her brother. He was warm and tight around her. Just like her own bum, except not her own, obviously.

"How's that feel?" she whispered.

"... you can keep doing it. If you want."

"Ok."

Celeste's finger slid deeper.

"This is... weirdly intimate," Lucin said.

"It is," Celeste agreed absently. "I think maybe it's kinda hot, even."

"Yeah?"

"Yeah. Like if I move my finger in and out like this...."

Lucin gave a small, involuntary moan. It wasn't like it was an insane, intense sensation or anything. But it was new and different, and definitely weirdly intimate.

"What about two fingers?" Lucin heard himself ask.

"Really?"

"I don't know. Will two fit?"

"You tell me. It's your ass."

"I'm new to this!" Lucin protested.

"So am I!"

Further argument was postponed as the heavy footsteps of Matilda approached from outside the room. The sibs froze right where they were as their robot caretaker came right up to the doorway. Matilda, in her deceptively delicate way, reached in and knocked on the door.

"You don't have to knock," Celeste said, rolling her eyes. "The door's broken from your last entry, remember?"

"It's polite though," Lucin said. "Even if the door's off its hinges."

"It's not. It's... it's nothing. It's a useless formality."

--I am doing laundry--

"Are you really?" Celeste said, nonplussed.

--I require your dirty clothes--

"Well have at them then."

Both siblings watched curiously as Matilda strode in, efficiently gathered Celeste's laundry, and marched out again.

"She really doesn't care about you fingering my ass, does she?" Lucin commented.

"Seems not." Celeste turned back to her brother's backside. "So... second finger then?"

"Yes please."

Two fingers was more of a struggle. It wasn't impossibly tight, but tight enough to slow Celeste down.

Lucin started giggling. Celeste, trying to maintain some sense of focus, nevertheless followed him as they both lost composure.

"Why are you laughing?" Celeste said while shaking from repressed giggling.

"You're laughing too!"

"You started it."

"It's...." Lucin paused and tried to take a breath, but kept just giggling despite his best efforts. "I don't know. It's just funny, isn't it?"

"... kinda. Should it be?"

"I don't know. I've never had a sister burying a pair of fingers in my bum before."

"Attempting to bury," Celeste corrected. "Not quite getting there. Keep laughing though, I think it's loosening you up."

"Yeah, that's part of what's funny. Just like, it doesn't hurt like you sometimes think it would."

"Well it's only fingers. They're little."

"True. I don't know. It's this whole confluence of different factors. From like, porn influence, and jokes people make, and how mildly forbidden it is. And all it really comes down to is my sister grumpily struggling to get her fingers in me."

"I'm not grumpy!" Celeste protested, before snickering some more at the ludicrous situation.

"You were grumbling."

"I can grumble without being grumpy. And I was only swearing at your butthole 'cause it won't cooperate right."

"Yeah. Funny."

"Hehe, yeah, ok. Fair enough."

Lucin's butt slowly relaxed more until Celeste was able to easily finger-fuck him with her two fingers. Lucin crawled right up on her bed, leaving his ass in the air, and relaxed and just enjoyed the experience.

"Having a good time, are you?" Celeste asked.

"You know, I really am."

"You're certainly drooling precum."

"Am I?"

"Mmhm. Shame I can't do anything about it."

Lucin sighed. "Yeah, and even though this feels nice, I don't know that I'll actually be able to cum or anything. That might get frustrating."

"Hmph, yeah. I'm kinda worried about that too."

Celeste pulled her fingers out and examined Lucin's butthole. It gaped just a little afterward, but closed up pretty quick. It accepted her fingers back in quite easily though. Celeste alternated playing with it some more, and giving it some exploratory kisses.

"God, I could do this all day," Celeste said.

"Really?"

"Yeah."

"I mean, I know it feels good for me and all, but you're enjoying it?"

"I weirdly am. It's... it's just hot. It's wrong and naughty, and maybe I like making you feel good."

"Oh." Lucin mused it over for a moment. "Can I try on you?"

Celeste's clit, already buzzing, sent a surge of pleasure and anticipation through her just at the mere request from her brother.

"Ok," she said in a faint croak.

"Yeah?"

"Yeah."

The siblings swapped places. Celeste got down on the bed with her butt lifted, her shirt falling toward her breasts and out of the way. Lucin got behind her, and at first could only admire the view.

"It might be just as well we can't do... regular sex stuff," he said.

"Why?"

"Because I'd be far too tempted right now."

Celeste's breath came almost as a pant. "Tempted to do worse than jerk off on me?"

"Yeah. Worse than that."

"Oh."

"You regretting some decisions?"

"Not even slightly."

Lucin grinned and dove in. "Good."

Celeste moaned loudly as Lucin's tongue met her butthole. The instant shivers it sent through her eclipsed her previous thrills. It was insane and kind of scary how badly she was into this.

Lucin, likewise, was addicted from the moment of contact. Or, indeed, from the moment of beholding his sister presenting herself so lewdly for him, so ready and eager for his touch. But definitely after tasting her, at any rate.

"We're in trouble," Lucin murmured.

"Yes," Celeste agreed. "We are."

Not that it stopped either of them. Lucin licked away happily, while Celeste cooed and encouraged him.

Lucin slobbered over his sister's ass before eventually trying to finger her. Sticking his finger up her really was only an afterthought, as he'd been having way too much fun eating her out. The combination of spit and lube let him easily invade her butt.

"Ohh, that's nice," Celeste said. "Try two fingers."

"So quickly?"

"Why not?"

Lucin shrugged. "Alright."

Like with his bum, it took more work getting two fingers to slide smoothly in than just one. They had some more giggles in the process, and Lucin couldn't help pausing in their efforts repeatedly to devote more kisses and licks to Celeste's ass. They did eventually get to a point of him easily finger-fucking her though.

"Mmm, ok, let me do you at the same time," Celeste purred.

"Yeah?"

"Yeah. Get up here."

There was some more laughter and several attempts at repositioning as they tried to each get a good angle. Getting their fingers up each other's bums at the same time required some cooperation.

Their eyes met, shining with lust, fingers deep inside one another.

"Cel?"

"Hm?"

"I kinda want to kiss you."

Celeste bit her lip. "I bet you say that to all the girls knuckle-deep in your ass."

"All of them so far," Lucin agreed. "Can I?"

"You may."

They came together, lips connecting in a beautiful display of sibling horniness and love. They were helpless against their desires. Probably partly because of the lack of cumming.

They pulled each other closer, helped by their firm grips on each other's assholes. They moaned into each other's mouths as they got a little too close and Celeste's pussy made electric contact with Lucin's cock.

Almost immediately they detected the approach of their infuriating but very specific guardian.

--Do not do that--

The siblings whimpered as they pulled apart, but did so quickly enough to halt Matilda in the doorway. Matilda waited a moment, then turned and left again.

"God she's a pain in the butt," Lucin complained.

"And not the good kind," Celeste said, wiggling her fingers inside Lucin.

"Unf. Maybe it's good though. We shouldn't actually... do that."

"Do what?" Celeste asked innocently.

"You know."

"I do. I wanted to make you say it."

Lucin narrowed his eyes. "We shouldn't fuck."

Celeste burst into nervous laughter. "Oh god, you said it."

"I did." Lucin pushed his fingers deeper in Celeste's ass. "We shouldn't, you know."

"I know. We definitely shouldn't."

Again their eyes met with distinct, smouldering intent. They kissed each other and made out in increasingly sloppy fashion. They couldn't grind on each other, much to their mutual frustration, but continued to explore each other's asses quite freely.

"Ok, enough," Lucin panted. "To the restaurant?"

Celeste, on the verge of suggesting the same herself, quickly nodded. "Agreed. I need to cum."

"Alright, let's go."

****

Much to Lucin's confusion, Celeste pulled up and parked nowhere near to the restaurant he assumed they were going to.

"What, are we trying a new place?" he asked.

"Nope. Just making a stop," Celeste said with a teasing grin.

"Really? Now?"

"Best time for it. While we're horny."

"We're always horny."

"Not like this."

Lucin and Celeste exited the car.

"What are...." Lucin trailed off as he caught sight of a nearby building. "Oh, sex toy shop?"

Celeste nodded. "Sex toy shop."

"I... alright, I could be into this. You coulda just told me though."

"What fun would that have been?"

"You think it's too weird if I walk in there with a boner?"

"I think it's weirder that you walk in with your sister."

"Yeah, but no one will know about that."

Celeste laughed lightly and took Lucin's arm. "Just hide behind me if you can't keep you erection down."

"What exactly is it we're looking for?" Lucin asked, mind already whirling with possibilities.

"Dunno. Some butt toys, mainly. All my toys are for my pussy, which isn't helpful at the moment."

"... how many do you have, exactly?"

Celeste grinned. "I'll tell if you will."

"What?"

"How many you got?"

Lucin blushed faintly. "I asked first."

"True. I have...." Celeste paused and counted in her head. "Seven, I think. But I really don't ever use two or three of them."

"Really?"

"Yeah. You?"

"I... two."

"Just two?"

"Well yeah. It's not... it's not the same for boys, you know."

"Pff, a silly double standard. We'll fix that."

Their discussion continued in more hushed tones as they perused inside the shop. It wasn't a big enough store to really have a comfortable discussion.