The bedroom's artificial light shone above Frisk's brown hair as they quietly sat on their bed. The only thing to disturb them being the sound of the far away traffic of the city. Frisk let out a sigh and glanced on their right to check the time. It was 11:12 PM.

After readjusting their hair which had gotten slightly in the way of their vision, Frisk took a bit of time to reflect on the fact that they should probably be going to sleep now.

As much as the temptation to stay up for longer was strong, they knew they would be better off making use of this weekend to catch up on sleep as they did not get much of it in the last few days.

Meanwhile, in their own room, Chara was looking around everywhere for their locket. It held a lot of symbolic value to them, and they had taken the habit of wearing it to sleep.

But today, they couldn't find it. Where could they had left it ? They wondered. Usually, either they were wearing the locket or they left it on their nightstand.

Growing increasingly frustrated, Chara started checking in the shelves or on the ground. Perhaps they had simply put it back at the wrong place yesterday ?

Suddenly, they remembered.

This morning, they had accepted to lend the locket to Frisk as a sort of lucky charm for their incoming exam this afternoon. And although Frisk had since then come back, they did not remember getting their locket back from them. Frisk must still have it.

Their locket must still be in Frisk's room, they concluded. Was Frisk still up ? If they were, they could make a quick stop to their room to take back their locket.

Frisk checked under their pillows where they kept their pajamas. After quickly unfolding them, they pulled down their pants and then their underwear in order to put them on.

When they stepped into the corridor, Chara noticed that there was still light in Frisk's room. This meant that they were indeed still awake.

Chara hurried themself to the door in quest of their locket and opened it, they did not however, take the time to knock first.

Frisk almost jumped out of their skin when they heard the door to their room open itself whilst they were not wearing anything below the waist. When their eyes met that of Chara, they reflexively turned away although they knew it was already far too late to prevent them from noticing their obvious lack of clothing.

Chara's expression rapidly changed when they realised they had walked in while their friend was undressing. They had not chosen their moment very well. They leaned back and mouthed a quick apology. 'Oh. Sorry !' Chara smiled.

As the two of them had once shared Frisk's body, seeing them undressed was nothing new to Chara. It was something they had gotten used to a few years ago already.

While they were sorry for the inconvenience they had just caused, the embarrassment that usually came with seeing another person naked did not really apply between the two of them.

Frisk awkwardly stared at Chara for a moment before rationalising the situation. It was alright. It was nothing Chara hadn't seen hundreds of times before back when they had one body for two. It wasn't a big deal…

"I… Uh… " They began, struggling to find the words. '"ts okay… " They eyes drifted down. "You can come in, i guess." Frisk invited them in anyway to do whatever they had to.

Chara gave one long look accross the room from left to right, eventually spotting that Frisk had left the locket on the side of their desk. They make to their way to it, but while doing so, their peripherical vision unintentionally caught sight of Frisk's sex which was no longer hidden to them by the perspective.

Now that they were older and had separate bodies, seeing this did not feel quite the same way as it did in the past… Chara was unable to restrain a slight blush, which was difficult to tell apart from their natural blush.

Frisk continued silently sitting there, waiting for Chara to take what they were searching for so that they could finish putting on their pajamas. But when they noticed the very quick look Chara took at their crotch and their subsequent blush, Frisk began feeling slightly uncomfortable.

They tried to brush this event aside as just another little incident that they shouldn't think much of. That being said, they did have to admit that Chara looked quite pretty when they were blushing like that.

Chara picked up the locket from the desk and put it on. They turned around again with the intent of thanking Frisk before going back to their room, but the moment they tried looking in their direction, they couldn't help but to get distracted and take a quick glance at their member again before they could force themself to refocus on Frisk's eyes.

Why did they do that ? Chara did not even know themself, but they hadn't been able to help it. One thing that was becoming increasingly clear to them however was that they were not unaffected by it as they used to be when they were children.

Seeing their companion about to say something only for them to be distracted by their naked body a second time made Frisk blush too as it became clearer that what Chara had been doing was a bit more than just another accident. Staring at their pretty face whilst they were looking at their member, Frisk suddenly felt it begin to stiffen a little.

Afraid of what Chara would say they if they noticed their growing erection, Frisk attempted to hide it in embarrassment by shifting their covers over their lower body. This was a futile effort as the bump of their now hardened sex was still easily visible through the covers from the first fallen human's position.

Chara felt a slight heat bluilding up in between their legs when they saw it. That was because of them, they thought. They had just made Frisk get hard.

They realised that knowing that they had caused this reaction was making them feel a little bit turned on…

They both stared into each other's eyes for a moment.

Frisk could tell that Chara knew. And that they knew that Frisk knew that they knew.

Frisk broke off the stare, feeling slightly ashamed. 'Im sorry ! I didn't mean to. I don't control it !' They tried to justify their body's reaction, not wanting Chara to get the wrong idea.

The older human giggled. "Its fine. Don't worry about it." They looked aside. "That was my fault anyway." As they kept talking about it, they realised that this whole situation was making them feel quite aroused.

They hadn't masturbated in about week. And looking at the state they had put Frisk in just by looking at their sex… There was no denying it now, they were feeling horny.

They wanted Frisk, Chara realised. They actually wanted Frisk right now.

Was that a bad thing ? Would it be okay if they…

Chara swallowed their saliva before walking up to the bed. "Its natural." They added as they approached closer to Frisk, who was still trying to hide themself with their blanket. They placed their right hand on the wall near Frisk's head.

Frisk's blush increased in intensity and they were now red as a tomato. Damn it… Why did they put their hand like this ? And why was this actually getting them turned on ?

"C-Chara ? I…" They tried to speak up again but got lost in the first fallen human's passion filled eyes.

After a second of non verbal communication, Chara felt their legs shaking as they inched their head a little closer to Frisk. Close enough for them to feel each other's breathing.

Frisk felt their heart pounding out of their chest before they slowly approached as well.

Chara took this as a signal to close the remaining distance between them and lock their lips together. Frisk wrapped their arms around Chara while the first human's tongue sought entry into their mouth. Frisk let it in before reciprocating. The two shared a long kiss together before finally running out of breath and pulling away, leaving a trail of saliva linking their mouths for a few seconds before gravity broke it off.

Chara brought their knees into the bed to join Frisk. They were both starting to sweat heavily.

"You… " Chara began. "You're turned on too, right ?" They dared to ask them, not without a little apprehension. Frisk slowly nodded, hardly believing Chara had really just asked them this question. They could feel their blood pumping through their lower regions as their partner still seemed to be looking quite nervous.

The older human was almost trembling. Could they really ask them that ? Or would it be a step too far ? What if they said no ? After all they had been through together and everything they had shared, the two of them wouldn't judge each other about anything anymore, right ?

"Can… can i… see it ?" They quietly requested.

Frisk felt a chill run down their spine. "Oh my god.", they thought.

Immediately, they felt the urge to say yes. Did they want this ? They asked themself. Their body absolutely wanted it, and when they looked at Chara… It... It made them think of some very inappropriate things right now.

Wow, they wanted this. Frisk finally acknowledged. They wanted Chara.

Timidly, they nodded again and moved their hands out of the way so that Chara could push the covers away, revealing their sex underneath.

Frisk spread their legs just a little, blushing hard while Chara approached their face closer to their erect genitalia.

It had certainly grown a bit more since the day Chara had gotten a separate body again when Frisk was 15. The older human couldn't help but wonder how it would feel like if they…

They could feel themself getting wet.

"Is it okay if i… ?" They wondered, approaching their hand a little.

Frisk did not even make any sound while signing them shyly that they could. The first fallen human calmly envelopped their dick in their palm before slowly beginning to stroke it, earning a few timid sounding moans from Frisk. They were making such an adorable expression while they did it, too ! Frisk seemed to be in such bliss from the foreign stimulation.

Their penis felt warm in Chara's hand. They kept gently rubbing Frisk for another minute. Making them breathe heavily whilst refraining gasps of pleasure.

When they eventually let out a little bit of pre, Chara found themself wondering how it would taste like. They felt like this was not enough. They wanted more of it. More of Frisk, more of their moans, more of the faces they made when they were being pleasured.

They took their hand away and looked back at Frisk's face before giving the head of their shaft a single unprompted lick, this time with their eyes filled with nothing but lust.

"Can i go down on you ?" They asked.

The words echoed in Frisk's head. They were proposing oral.

"Y-yes, please !" They failed to hide their excitement at the thought of letting Chara blow them. The latter flashed a mischievous smile before opening their mouth and wondering for a moment how much of it should they try to take in.

Chara decided to start slowly and only inserted the tip into their mouth. They started by giving it a few slow licks before pushing a bit further down in and swirling their tongue around it a few times, earning another groan from Frisk.

Chara didn't really know what they were doing that much other than they should use their tongue and avoid touching it with their teeth, but if Frisk's reactions were anything to go by, they were probably doing it right.

With newfound confidence, they pushed just a little deeper still before pulling it almost all the way out, leaving the throbbing sex wet with saliva. Then, they envelopped it with their mouth again. They started slowly bobbing their mouth up and down Frisk's member.

The latter had closed their eyes so that they could focus on the sensation better. The way Chara's lips would suck them in so that their tongue could flick around their sex, providing them with pleasure the likes of which they'd not felt before. And the noise they'd make each time…

Chara's mouth felt so warm… and so wet…

As they got more comfortable with the blowjob, Chara progressively got more into it until Frisk could feel the head of their sex grinding against the roof of Chara's mouth with every bob, sending shivers of pleasure down their spine.

Opening their eyes again, Frisk brought their left hand to Chara's head. Not to push them in as they prefered to let them do it at their own pace, but to gently pet Chara's hair and trail their fingers through it affectionately to signal them that they were doing a great job at making them feel good.

"Please, don't stop." Frisk requested in between two moans once Chara picked up their speed slightly and settled on a comfortable rhythm.

Chara kept on sucking passionately, enjoying themself as well. Frisk's groans were music to their ears, only prompting them to keep it up further.

Frisk was really getting into it too. Chara felt them begin to slightly thrust their hips towards them with every bob.

As they felt Frisk's body start to shiver and the moans increase in volume, Chara wondered wether Frisk was getting close.

Chara continued for just a little longer until…

Before they could make it to the point of no return, Frisk grabbed Chara by the shoulders and pushed them back against the bed, positioning themself above them and reaching for Chara's shorts. They gave them a questioning look, waiting for a sign of consent so that they could reciprocate what Chara did to them.

Chara nodded and helped Frisk get rid of their shorts whilst pulling up their shirt and undoing their bra, revealing their chest. Frisk nervously reached for their companion's underwear before Chara grabbed their hand with their own and they both pulled it down together.

Frisk stared at the slit in between their partner's spread legs, uncertain on how to proceed. They wanted to pay Chara back, but they were slightly afraid of doing it wrong. They rubbed their finger against it a few times before deciding that they were better off asking Chara about what they'd like rather than relying on instinct and possibly not meeting their expectations.

"What should i do ?" They asked. Chara found it very cute how shy they looked while asking that.

"Just… Start with your finger for now." They requested.

Frisk nodded and probed Chara's entry with their index before very slowly pushing it into them, on the lookout for Chara's reactions in order to figure out what felt good to them. Chara gasped inwards.

Once they made sure everything was good for them so far, Frisk started gently pushing in the rest of the way, then back out. Chara's bodily fluids wetting their finger and sliding down their palm.

Chara bit their lip, they initially prompted Frisk to just keep going. But not faster. At the same pace. Frisk did their best to continue to follow the rhythm, encouraged by Chara's occasional soft moaning. Chara felt… smooth, and slicker as they went on.

"T-try adding a second." They eventually requested with a trembling voice.

The eight fallen human paused for a moment to join their middle finger to their index, palm facing upwards, before pushing in again. Going slightly slower this time to let Chara time to adjust to being stretched further before progressively working their way back up to the previous pace which Chara had found pleasurable.

The older human moaned quietly in ecstasy, like a loud whisper, while Frisk fingered them.

Eventually, Chara exhaled slowly and squirmed to reposition themself once Frisk's fingers exited them, moist with their juices.

The first fallen human spread their legs a little further and shivered in anticipation as Frisk brought their face between them. After a quick eye contact in search of approbation, Frisk slit out their tongue.

They began by gently licking their pussy and getting acquainted to the taste. Then, they carefully reached for their clitoris by stretching the tip of their tongue before they gently sweeped it accross the sensible organ.

Chara let out a stiffled moan and blushed somehow more than they already were. They tilted their head towards the left and they closed their eyes.

Then, Frisk attempted to infiltrate their tongue into the first fallen human's opening. They swirled it inside, aiming to reach multiple different angles but quickly went back to licking the clitoris as this seemed to be more blissful to their partner.

Chara could feel their pulse in their groan. They gasped in pleasure multiple times as they could feel a flame burning hotter and hotter the more their companion kept going, both in their cheeks and in their crotch.

Frisk started moving their tongue in circles. They first go clockwise, before starting to alternate between clockwise and counter clockwise every few seconds.

The first fallen human felt a gentle heat rising in their body as the accumulated tension built up inside them.

It rose and rose until it reached a tipping point and Chara came. A warm fuzzy feeling spread through their body like a tidal wave. A sweet tingly warmth that for a few moments, prevented them from thinking about anything else than how good they felt.

It subdued very slowly and Frisk pulled back, but Chara did not leave them much time before raising their torso back up and grabbing Frisk's head to give them another kiss, mixing their tongues and their passion. They still felt that soft itch down their nether regions, that ache that awaited to be fulfilled. They were not done with this, they wanted it again, they wanted more.

When they pulled out of the kiss, Chara pushed Frisk's chest to pin them down on the bed and got on top of them. They wanted to take this all the way. The first fallen human reached for Frisk's sex, still hard and wet from their blowjob, and pointed it closer to their entrance, waiting for approval to slide down and merge their sexes.

In the middle of the excitement and arousal that came with the thought of having sex, a doubt rose up in Frisk's mind.

"Wait…" Chara felt concern in their voice. "Shouldn't we use protection for this ?" Frisk wondered, afraid that having unprotected intercourse on impulse may be a bad idea.

Chara had to concede that they had a point. They had no intention of taking the risk to get pregnant if they failed to pull out properly for their first time.

Well, Toriel did buy a box of contraceptives and stored them in the bathroom a couple years ago in case either Chara or Frisk ever needed them someday. She was very understanding regarding these things. But given that she would probably notice fairly quickly if one was missing and that Toriel knew neither of them was seeing anyone, it may lead to some unwanted complications too. They guessed that if they wanted to avoid her asking herself any questions, they could always just replace that box with a brand new one later on ?

Suddenly, Chara had a much better idea.

After all, it was Frisk they were about to do this with…

"We don't need that." Chara responded with a large smirk.

"What ? But-" Frisk felt anxious and confused, but before they could question further the first fallen human's answer, Chara reminded them of the power they held.

"You can just SAVE."

Frisk's expression lit up when they realised what Chara was getting at. That power allowed them to not have to face any consequences for their actions, having unprotected intercourse would be no exception. As long as they just LOADED their SAVE file afterwards and undid everything, there was no chance they could impregnate Chara even if they came inside. The SAVE power was a contraceptive of its own.

They both shared a knowing look and smiled lightly before Frisk closed their eyes to try and focus on their determination. They reached out with their arm towards something on their right Chara couldn't see.

FILE SAVED

Frisk refocused on Chara's face and softly caressed their cheek before giving them a nod as a signal that they were ready. Chara readjusted their position on top of Frisk. They were nervous, a little scared even, but also terribly impatient and excited. They rubbed Frisk's sex against their opening for a few seconds without daring to slide it in.

"Do you feel ready ?" They asked, more in search for reassurance than anything as they already knew what the answer would be.

"I… Im ready whenever you are." Frisk grabbed Chara's right hand with their left as a sign of trust and to give them courage. They felt a sort of warm flood of invigorating energy, a sense of anticipation, and a breathless longing. They feel tense, but also oddly relaxed at the touch of Chara's smooth skin.

The first fallen human exhaled slowly and stretched their trembling legs just a tiny bit further because they slowly lowered themself onto Frisk's shaft. The latter let escape an acute light moan as they felt their penis penetrating inside of their folds, the touch of Chara's walls sending electric-like waves of pleasure into their system.

Chara bit their lip again. They could feel their partner's sex throbbing inside of their vagina, emanating a gentle tingly warmth that made them feel… Full. They both stayed like this for a little while, barely even moving, just enjoying this feeling of union. Frisk wrapped their arms around Chara again in order to pull their naked bodies in a little closer together.

They were like in a cocoon of their own, a cocoon of intimacy and bliss. It was as if they had become one once again, just like they had used to be years ago.

Eventually, Chara lifted themself up little by little until Frisk was almost ready to slip out of them before lowering themself back into their cock. They felt Frisk holding their hand a little stronger when they did. Soon enough, they quickened the pace. Frisk felt fairly wide for Chara's narrow opening, which squeezed their member tightly every time it thrust inside them.

Every back and forth movement was accompanied by a slick sound as Frisk's throbbing sex plowed through Chara's folds, making their companion squint and moan slightly, feeling as if electricity was tickling their spine.

Frisk tried to speak up to voice out their feelings but all that they could muster were a coupled strangled moans. Being inside Chara felt so warm ! And tight ! And wet ! and good ! They were incapable to describe what their virgin body felt with another word than incredible. They wished that moment would last forever.

Thirsty for more, the pair accelerated just a little more until Chara found a pace which made them feel really good and kept at that. They could now feel this same fuzzy electric sensation shooting more towards their nether regions as another chill of excitement ran down their spine.

As Chara involuntarily leaned further towards them, Frisk went for another kiss. While they gave into the kiss and their saliva mixed together, they began feeling tension throughout their body start accumulating towards their crotch. As the feeling intensified and they pulled away from the kiss, Frisk tried to warn their partner.

'Chara ? I think that soon i… im going to…' They managed to articulate.

'Ahh~ I.. I think im getting pretty close as well…' Chara responded after being interrupted by a groan as they were about to speak up.

The first fallen human did not slow down nor stop riding them, and the tingly buildup Frisk felt grew exponentially until it reached their limit.

Frisk squeezed both of their warm moist bodies tightly together and moaned into Chara's ears as they came inside them.

Chara could feel Frisk's body spasm as their moaning faded out. Frisk's sex was twitching, pulsating into their pussy at the rhythm of their heartbeat, shooting out semen into their womb as they kept thrusting while riding out their orgasm. Sensing their insides being filled felt incredibly satisfying, Chara felt just about ready to burst again too, but they were just not quite there.

Not wanting to let Chara feel left out, Frisk kept on thrusting along with them even after they were done and despite their penis now feeling very sensible due to their recent climax. They kept up all the way until a few moments later, they felt Chara's walls clench around their shaft and their companion reached their second orgasm, screaming out in bliss as the wave of soothing warmth echoed through their body again.

After their orgasm subdued too, Frisk and Chara just laid there in this position for some time, their arms wrapped around each other and breathing out slowly, wet with each other's juices and recovering from orgasmic bliss. Finally, Frisk pulled themself out of Chara, leaving a few traces of their cum leaking out of their entrance and some filmy white liquid enveloping Frisk's slowly softening erection.

For a little while, Chara stared at their oozing vaginal opening before speaking up again.

"That… That was incredible." They breathed out and gave Frisk an affectionate peck on the cheek. They both wore an undying grin. "But i think you should probably LOAD now…" Chara made a head movement towards their crotch. They wouldn't want that to stick around. As much as what they'd just done has likely been the greatest thing they'd ever felt, these events would have to be undone now in order to avoid... potential problems in the future.

Frisk nodded in response, and quickly did just that. After staring at Chara's body one last time and still with a warm blush, they closed their eyes and tried to LOAD their file.

FILE LOADED

Time has been rolled back by not more than just a dozen minutes. To the last time they'd SAVED. Glad to have been able to experience their first time with each other, Frisk and Chara stared at each other happily before they shared a hug.

However, whilst they did, Chara felt Frisk's sex poking them near the stomach.

Right. Since they LOADED back to before they did it, but after they'd already done everything else that lead up to it, their bodies were now back to being fully turned on and to urging them for release.

…

They shared another knowing look. They both knew the other was thinking what they were thinking.

Without another word, Chara pushed Frisk's shoulders, pinning them onto the bed, and got on top of them again. And with renovated stamina from the LOAD, they ended up going for another round.

And then another one.

And then another.

As long as they kept LOADING, their bodies would never get tired.

They lost count of how many times they had sex that night.

Author notes :

I am a sinner.

And also an idiot. I've made this for valentines day, but although i did post this on ao3 on that date, i forgot to publish it here. Oops.

But hey, if you've read this far, then that means we are both sinners :D So hope you've enjoyed !