I do think a lot about the greater context in the world surrounding something like fooling around, though I also think this isn't something exclusive to incest at all! The difficulty, secrecy, consequences of trying to have sex when young are really one of my favorite pressures to consider... I guess it's a part of life I remember vividly myself. I like that in order to do ANYTHING as a kid or teen, you kind of have to be enterprising and duplicitous, you have to be motivated, you have to be clever, and you have to want it so badly that you are WILLING to risk so much, likely punishments as extreme as total separation, ostracization, or destruction of your social circles, your family, the trust others have in you (depending on your community). That's kind of what is so charming about puberty... it creates that imperative sense so extreme, you might just blow up your whole life to have something. PLEAAASE!!!!!!

I like chatting with friends or listening to candid podcasts where people can talk about like, how much hand and mouth stuff was going on at the back of the Gym Factory, how a back corner of the Baptist community pool was a hotbed for teen fingering, games like Snugglebug or 7 Minutes in Heaven, CONTRIVANCES!!!! And the people doing this are so rarely TRYING TO GET AWAY WITH sordid incest, it's BAD ENOUGH to be trying to secretly fuck the neighbor girl in your spider-infested Fischer-Price plastic house in the backyard!!! You go to a shitty movie about to be out of theaters with your friend in the HOPES the theater may be EMPTY so you can get some touchhhh. Your parents drop you off and don't know your nefarious plans. PUBERTY!!!!!

I was watching a video recently about playgrounds throughout history, and when it depicted the era I was familiar with-- very interesting sprawling wooden castle-like structures-- they pointed out parent's complaints about these beautiful playgrounds: the lack of clear sight lines at all times. I laughed out loud because I DO have memories of hotdogging behind the walls of one of those as a young teen. If ONLY I had a playmate in the Kid's Castle times... so many pipes to hide in.

That's kind of the operative fantasy...

In Deltarune itself, Asriel was reprimanded and made to go to church repeatedly just for being kissed by a girl as a teenager (we don't even have a gauge of how much he wanted it to happen). It isn't as if making out with Dess, Noelle, Catty or Bratty, would go smoothly.

Which brings me to another layer... trust and expectation. Some kids are allowed more freedom and leeway due to good behavior, or apparent disinterest in dating or sex. One may be able to blatantly get away with more or less! Everyone is scrutinized differently, effecting difficulty levels.

Maybe we could imagine Noelle has high trust; her family doesn't imagine her misbehaving, she is left home alone a lot. The household itself is restrictive, rarely allows any guests seemingly, she is meek, so the idea she is going to be getting railed behind Ice-E's is .... not of concern. She's not monitored very closely, even to a kind of neglectful extent (locked out of her house, needing Kris's help to break in...).

Where is Kris's trust level at? They are mischievous but, childish and clownish. I don't actually think anyone in the Holiday-Dreemurr households see Kris as a potential sexual menace... I think the aspect of being a human could also play a role? The Eunuch Jester.

In real life being a queer kid kind of rules in some ways because uhm, it's just not a concern what 2 girls may get up to. My house only really had a real about 'boys' being over, the door needing to stay open. Whim and I also both come from neglectful houses where we could get away with a lot, because our parents... didn't ... have the attentiveness. I will be real with you, my mom was a meth addict, it was lucky if she could get me to school enough days for me to graduate at all, so. Like. Many factors in households that determine how easy it is to get away with fucking around.

*steeples fingers* So... if we think about Asriel and Kris... let's imagine they're both committed to keeping a secret, at all costs. Separation is not an option, they couldn't bare it... Lets say they work in close concert with one another to consider all liabilities and risks, and acknowledge the possibility of pain and-- WAAAAAIT A MINUTE, THIS GAME IS ALREADY ABOUT SOME SORT OF INSANE CONTRIVED SECRET PROMISE IN OUR HEARTS I'M WITH YOU IN THE DARK!!!!!!!

... so what is even different? What difference would it make if Kris and """""Ralsei""""" were fucking in the dark? Or for that matter, if you're not incest-inclined, Kris and Susie, or Kris and Noelle! Kris is already secretly terrorizing Noelle in the Weird Route, she's already choosing to not report on the matter to a parent or teacher or something.

... I think in mmost ways, keeping mommy and daddy unawares of the incest kissy is easier than many other things... it's harder to trust outside agents, kids gossip, and it's much, much harder to be all alone with someone not in your family. Kris and Asriel share a bedroom... why couldn't they kiss eachother, what's stopping them? It's almost harder for me to imagine a circumstance in which they get caught. Couldn't they come up with almost ANY excuse as to what they were doing, and wouldn't their parents much sooner conclude they misunderstood something? I generally imagine even if one technically 'walked in on' something that it would be rationalized by any parent as completely non-sexual ... because it's Occam's Razor in this context. Teens are smart, they're often doing hand and mouth stuff 'cuz it's easy to quickly disengage from, hide, pretend you were doing aaaaanything else. This is also related to why I rarely ever depict or think about like, fullbody nude ass crazy 10 sex toys bucket of lube porn, lol. I'm inclined to envision fully-clothed, baaaarely peaking cock out from top of waistband, eaaasing a skirt up, pushing panties to the side, kind of stuff...

I really think Kris could be balls deep in Asriel's mouth beneath the bedcovers, and mom could knock, and they could work out any excuse-- even the clumsiest-- and what reason would mommy have to not believe it? One would be 'on the lookout' for something like that likely only if there were some sort of... obvious deterioration of mental health observed, unusual behavior, acting out, worrisome signs (which-- again-- Kris is actually already exhibiting in these Dark World Playtimes for theorhetically completely non-sex related reasons... mommy is already asking Kris's teacher and the hospital if they seem OK lately)...

.... so in all honesty I don't often play with entire scenarios or RPs where mommy and daddy find out! I CONSIDER it an aspect, like the characters would... but it's also an external threat that can be controlled with care, and I think-- IF ASRIEL AND CHARA COULD HIDE A LONG PROTRACTED ASSISTED SUICIDE FROM THEIR PARENTS SUCCESSFULLY WITH NOT A SINGLE CRACK-- ohhh a little nookie is a piece of CAKE, isn't it????

Conveniently Kris/Asriel and Chara/Asriel already engage in the art of doing some secret dark shit their parents would be horrified of!! IT'S ALL MY LITTLE GAME!!!!! I live HIGH on my kingdom.

The actual question... 'What would parents do if they found out'... is a little boring in practice. Little nuance to it. They'd have to figure out separation, I guess, try to control the situation? Asriel and Kris's parents are already divorced so it wouldn't even 'break the family'... Asriel is also already over 18 so banishing him from contact for the rest of Kris's childhood (or at least while appropriate measures are taken) is easy. Kris has seemingly already attended therapy at one point, back to it I guess. As for Kris and Asriel, well they'd surely do what any starcrossed lovers do... everything in their power to circumvent the separation........................ ? but again aren't they already doing this in canon ? just coping with the separation of college alone... they've been described by Alphys as talking for hours online every night... if I'm right in my suspicions that Asriel is the Phone Ghoul Voice, then Kris is already discreetly communicating, phone left with no trace of communication after correspondence ... mommy doesn't know...
Kris is out here slashing tires and cutting the internet to the town for the present 'plan'...
one must imagine an incredible Krissy-kun capable of thwarting any and all boundaries set in place. Such a beautiful mind.

... I'm more interested in playing out something like Dess or Noelle catching something, which both feels more likely (proximity...), and is just more interpersonally interesting, as their reactions are less rote and predictable. Nobody wants to destroy their friend's reputation, life. Noelle would have all of the background information on Kris and Asriel's childhood... how 'surprising' it is to her may depend on so many things... her age, and, what she's capable of conceptualizing, how she finds out, what exactly it is she sees. I like to think she would keep a secret, given that in Weird Route, she's keen to hide Kris's behavior, even if it frightens her directly. Obviously protecting Kris is more important than reporting them!
I think she would want to fully understand the situation, and hear from Kris and Azzy's own mouths, before she makes any snap judgements...! And I would like to think Kris and Azzy would want to trust her, wouldn't want to see her as an enemy or threat to their peace.... Surely, in this crazy scenario, they could talk it out.
When I consider how anyone reacts to things, I consider how much social mores mean to them... and how often do social mores feel 'right' or 'justified' to them in their own lives? Do they feel rules exist for a reason, do they believe rules protect us? Or do they break rules habitually, or do they WISH they broke rules habitually? Do they already love somebody or something controversial to love? Do they have interests or hobbies that are hard to explain, or misunderstood, or that their parents or peers would react to badly?
Noelle... I would imagine her thoughtful, contemplative, capable of looking back on years of memories with this new context, trying to make sense of this. Wouldn't the story of an adopted human falling in love with its monster brother seem kind of... fairytale like, romantic? Like something in a video game or movie or book...

Jury is OUT on Dess, but she's committed to disobey rules herself all the time, right? I hope she could just laugh and bully them about it discreetly or something. Even if she was rough around the edges, I believe all of them were good friends. Maybe a bit of like... don't you freaks corrupt Noelle in any way... KEEP THIS FROM HER SWEET MIND... SHE DOES NOT NEED THE DARK VISAGE OF YOUR HAND AND MOUTH STUFF!!!!

I actually think Susie would be Understanding, partially due to distance with the idea of 'family'? She's probably more atuned than anyone here to the interspecies aspect, adoption case thing... I could imagine her mind very crudely concluding "well it's not really bad, you're not even really related at all..."... she likely doesn't have much context for what growing up together with a sibling would feel like, or what 'makes it wrong'. She's not very literate or worldly. She would be more inclined to believe something that preserves her friendship with Kris, the thing she values ... as opposed to something as meaningless in her own life as 'society' or 'morals'. She's a misbehaved and misunderstood person... if it was made obvious this was important to Kris in some way, and Kris was obviously afraid of others finding out, of course she'd err on the side of "whatever, then society is wrong and stupid, what do they know about what's good or bad? Society makes people judge me shittily for stupid reasons too... you're not hurting anybody, if you both wanna do it then whatever, right?"

Forcing myself to think about the parents a little longer for you. I guess I think Asgore seems to me more capable of coming around to the idea !?!? but Toriel is the one with more concrete concepts of right/wrong in Undertale... Asgore kind of just does what is convenient, and what creates the least immediate conflict (does this make him soft, or a coward?). If Toriel went nuclear on the situation he'd probably align with her, but he'd also probably be unable to really muster up any punishing atmosphere for Asriel or Kris in practice... if anyone was going to look the other way, it would probably be Asgore... he would surely be torn between letting down Tori, or wanting to stay closer to his kids. In the end he would probably disappoint them all with useless fence-sitting, like in Undertale. Not supporting anyone enough to make impact.

Toriel has a stronger sense of justice and morals, she is much more capable of altering all of their lives, breaking the peace for the sake of something important. She has the greatest concept of consequences, harm, WHY it's not OK. I don't think she would hate any of her children; she could see this as a kind of foolishness... not villainy... but nonetheless I'm sure Asriel is held to a standard, being the older sibling, and the one with a kind of history of accusations as it is in canon. Kris is already babied and would be talked to and assigned professional help, boring but how it would go. In a situation like this, the 'responsible' and 'rational' thing to do would be to see Asriel as the perpetrator.

I guess if it got that 'intense' the only 2 options for our lovers are
1.) lover's suicide time.
2.) run away together

or maybe 3.) make a secret alternate world we can fall into hidden in the dark where none can see, where no one can tell us it is wrong to fall in love.

Do you ever think that for one reason or another Kris and Asriel may already be going nuclear, anyway? Do they ever not go nuclear...
overattachment and the expectation to 'grow up' alone might be capable of motivating them towards an insane escapism fantasy and dark plot....