quib

Classic Sans :

Awkward is the best term to describe him during this time, Sans does not like being out of control of his body in any form and his heat especially as it progresses is gonna be an experience to say it lightly

Generally hard to be easy and laid back when your body is not uh....not that

He deliberately does not tell you about it, avoids sex like the plague, and is just generally acting weird, until you either put the pieces together or he genuinely thinks he might pounce on you at any moment

He personally admits he normally rides these out alone and doesn't know how he'll act around a partner

Now that you're here though, things are different

A brief chat mainly to ease him into it as you genuinely trust Sans regardless of what pheromones are doing to him

Once things get started well? It is a lot

Sans had previously been attentive during sex don't get me wrong, however he just kind of treats it like anything else he does. Chill and laid back.

During his heat? He's clingy, impatient and needy, going for several rounds at a time, begging to pump you full of his cum, groping at anything and everything.

Naturally rougher as a result, though it's less intentional and more out of sheer desperation because even without extreme horny brain you turn him on so fucking much

"sorry baby i can't help it-" being said as he fucks you through your fifth orgasm of the day, he's cum inside you many times at this rate but his body screams for more and for more of you specifically

When he does tire himself out or manage to calm his urges enough to think properly he does help clean up, order take out and cuddle. The occasional pun here or there, "i'd make a dick joke but that'd come across as cocky wouldn't it"

But per usual cool down periods do not last for that long, you have woken up before with him grinding against you nearly whimpering as he needs another round

Never been extremely heavy on dirty talk, but he's a lot more quiet during his heat cycle outside of grunts and moans. When he does speak it's normally making sure you're okay, praising you, telling you he's close.

Occasionally he'll mumble things to himself likely things he didn't mean to say outloud, stuff like how good you're gonna look knocked up, how much he wants to fill you right now, and that he wants to breed you so fucking bad

Kinda...protective in a way he just isn't, even when he isn't balls deep inside you. Hovering over you, attending to your needs outside of the bed room attentively, and on the off chance you need to speak with someone else. He is there, as if waiting for the moment he's needed to intervene.

Definitely some nesting behavior, that's pretty endearing.

Underswap Sans :

Does tell you about it beforehand, blunders a bit, sort flustered, but he wants a gameplan before anything else and he did not want to risk scaring you off.

You get the whole run down, how long the cycle lasts, what to expect, the likely good if a kid happening, etc, etc.

You start out very informed and you do prep for it accordingly, though Sans did insist that you could just sit this out as he is aware he becomes a lot during this period

And boy howdy was he not fucking joking

This man has some serious energy, combine that with his over energetic nature in general and his need to please you feel like you're basically rendered into his personal fleshlight as he pounds into you over and over

Anytime he cums, he simply just doesn't stop. Still hard and thrusting into you like jack hammer, as if the previous orgasm was just a little hiccup.

Don't worry he's just as eager to please you as he is himself

Sans has always been a bit of a worshipper in the bedroom regardless of who's on top (you two switch it up quite a bit), he really gets off on just knowing he's making you feel good and likes to praise you cuz he looooooves you

He's sickeningly sweet sometimes and on his heat

Every orgasm you have is getting milked outta you

He'll happily play with with clit and tits while pounding into you, man handling your form in passionate manner. Anything to make you moan louder and cum on his cock again

Very chatty too, not that he was ever quite but it's full force here. On and on about how pretty you look stuffed with his cum, how you're so tight, how he wants to never stop and how he's going to keep making you feel so good

Due to his high stamina cool down periods almost like never happen, he will still stop and tend to your needs when you're hungry or tired but he has a raging hard on the entire time.

You work on a compromise of him jerking off and cuming on your nude form either when asleep or utterly wrecked with your over flown pussy needs a break

Which while at first he doesn't seem that thrilled about the idea, changes his mind as he really likes the idea of you being covered and marked in his scent.

It's less out of jealousy and more out of pride to mark you a deliciously nude way

Underfell Sans :

Would have told you about his heat....if he remembered

You're both kinds thrown for a loop by it, you more than him honestly. But thankfully you at least knew monsters did have heat cycles so it wasn't as out of nowhere as it could be

Though at first it did just seem like just Sans but hornier

Sans seems to have two main moods that be flip flops in-between, VERY aggressive in which he fucks you with malicious almost violent intent telling you that he owns your pussy, that you're his little fuck doll and he's going make sure everyone knows it

And a big massive softie that's extremely sweet and lovey dovey to you. Something that was normally only happened in very small doses or when he's utterly shit faced

It's not just praise but adoring you, talking about how much he loves, you that he's lucky to have you, how he just knows you're going to make a great parent

The whiplash is real, especially since sometimes he'll change his tone half way through fucking you. It's never entirely clear what sets either side off, other than occasionally his sweet side normally happens once he's cum once or twice

Very...possessive during it all, constantly rambling about how you belong to him and he'll kill anyone that even thinks about doing this to you

You don't know how much he'll actually act on that threat, but it's probably a good thing that neither of you are able to get out much.

But frankly while he's like this he would be willingly to fuck you someplace public tbh

So. Many. Fucking. Hickeys. You're covered in them by the time it's all over.

Cool down periods he does his best for after care, but like....he's very quiet. Almost like he feels guilty, especially at the sight of all the bruises you have. Which you will have to reassure him that he didn't cross any lines and that you liked it

"you're really some kind of freak ain't cha?"

"Your freak."

Horrortale Sans ;

Primal and animalistic are the best terms to describe him while he's like this.

Before the famine heats were no big deal, now however the term "wanting to fuck like animals" has never been more accurate

Sans never told you he got them, but you learned about them via other monsters so you were prepared on some level and even a little intrigued

Once a monster sets his sight on a mate, they'll frequently hunt them or fight off any other possible suitors. And given how you and Sans like to play Prey and Hunter, this allows you take things up a notch

The moment you know he's gone into heat, you run, you hide and he comes after you. It's a hell of a thrill, especially since you know it guarantee a better pounding once he finally gets you

You shifting around in the forest, sneaking around before you hear a husky voice call out "i know you're here sweetheart-"

You attempt to book it the other direction but the only thing you can comprend is a simple phrase before you're pinned to the ground

"gotcha."

The way you're fucked is brutal, he's never been gentle really but this is something else. Your entire body quakes with his thrusts, you're screaming as his cock is jammed against your g-shot and nearly rendered to tears from it all

He bites too, not just bruising you but definitely drawing blood then lapping it up with the same feral hunger that he fucks you with

Not very talkative, mostly just growls and groans. Only occasionally barking out "mine" or a "you're not going anywhere sweetheart" if you attempt to squirm away from him

Not that you really want him to stop but the struggle turns both of you on, he likes working for it and you like driving him up the wall to be honest

You're brutally fucked outside, clothes ripped off you, covered in bloody bite marks, pussy full of his cum, on the verge of passing out until he seems to either we decide to let up or is tired himself. He'll drape his coat around your naked form then carry you back to his place

If anyone attempts to stop him they're killed on sight, this is his mate and no one gets to touch them during this time.

When you wake up there'll simply be a low growl of "told ya you weren't going anywhere" before the cycle continues.

He does halt to care for you, you're his mate after all, but again weirdly silent throughout most of it.

It'll be a while until he's more chatty again, it's best to reassure him you were into his somehow more violent and extreme side of him.

Underlust Sans ;

Literally just his entire personality dialed to his natural extreme

Also doesn't think to tell you simply because he forgets it's not a common thing and to be fair it takes you while to notice

It's not until you're ten round today that you ask if something it up as while yeah he's got serious stamina and loves to fuck normally his dick would be a little soft by now

"Babe please tell me you didn't take some monster viagra-"

It makes him laugh before he breaks it down for you but also assures you there's no shame in tapping out and that monsters down here have ways to handle this without a partner

You take it as a challenge especially as he tells you it's not a challenge

It's one you enjoy though

The shift is his personality are far more subtle, rougher, a bit more dominant, and extremely fixated on pumping you full of cum. Like extremely fixated on it.

And whether it's the heat or some other factor you're not accounting for he cums a lot more than usual. Sometimes you'll just pinned down feeling his cock gush waves of his seed for several minutes as it fills you up.

He praises you through it all, telling you how good you are for him, how you take it all so well, and reassures you when it's almost done.

Your stomach looks more than a little bloated with it glowing with all the magic he just pumped into you and he definitely has a toy blog that helps you keep all of it in there

When you need a break from getting your pussy filled, anal play and oral keep you mouth entertained. You try swallowing his massive load but you end up having plenty spill out then the rest paint your body

And Sans looks super smug after wards the entire time

Definitely likes to tease you when he can, "bet you've never been fucked this good before huh?" said playing with your overstimulated clit while your whole is still plugged with a belly full of HIS cum

Having the most control over himself and already being a king of after care you're pretty much set when you do need a break for real

But you can't help being cheeky when you two are cuddling then you feel his erection rising up again

"You having fun?"