Swapfell Purple, Swapfell Red, and Underfell skeles reactions to having a kid that acts like a villain but really just has a hard time processing and expressing feelings? Evil laughter, plots world domination, lots of pranks that they boast about being a part of their masterplans,acting like they don't care about anything or anyone. And it is convincing until they find out the kid cares for stray kittens they hide in their closet. Cue kid's denials. Sorry if it is too specific. Have a nice day.
Nah, don't be sorry for being specific, it actually helps me out a lot more than you think. If you tell me what you're looking for then I can make sure I'm actually giving you what you want. You gave me some wiggle room so the answers won't be too similar, and I actually think the prompt is really, really cute. Also, you're the first person to ask for my Fell boys, so I hope you like them!
(Underfell Papyrus) Bamf:
Bamf sees a lot of himself in his kid and is really proud of his little mini me. When he was younger he used to act a lot like they do now. He wasn't really allowed to process his emotions due to how he grew up, so he'd put on an air of confident standoffishness and assholery around others, only getting to work on things when he was alone. So he gets it, and does his best to encourage his kiddo in whatever they do, giving them the time they need to process things their way. You wanna laugh like a cartoon villain? We're going to practice evil laughs together until you get it just right. You've come up with a plan to conquer the world? Let me just look it over for any holes or blind spots. Unfortunately, much like Sadie's mom Barb from Steven Universe, he has a bad habit of being overly supportive. He wants his kid to be happy, driving them to be the best at what they do, which can lead to the feeling burnt out and unable to fulfill his high Hope's and expectations. He'll never let his kid pretend not to care though. This is the surface and they don't have to live like that anymore. If something hurts, then it hurts, even if you don't know why.
When Bamf was just a bitty bones, he hid a kitten in his closet and raised it himself when his brother Fell told him that they couldn't afford to take care of it. She was a pitiful white furball that eventually became his truest companion. She was dubbed Doomfanger, because someone as terrifying and awesome as him had to have a just as terrifying and awesome of a pet, but he calls her Doomie when no one else is around. When he find out that his kid is doing pretty much the same thing he did, he gets really proud and feels like it's something else they can bond over. He tells the kid that they don't have to hide the small litter of kittens in their closet any longer. Doomie winds up adopting the litter as her own and soon the house is over run by a small army of kittens that both dad and child dote on together.
Fell gets it, he raised his little brother Bamf when they were bitty bones; he's dealt with this once already. The fake accents, the evil cackles, the plans for world domination, the pretending not to give a shit about anyone else because they're scared about what others think about them. He gets it, really....it just...gets annoying sometimes. He's totally down for diabolical prank wars with them though. Fell is pretty content to let his kid figure things out on their own, and when he's not, his involvement is a lot more subtle than his brothers. He's got ways of making his kid open up to him that'll make them think it was their idea the whole time.
Let me just say, that Fell hated his brother's cat, he thought she was evil incarnate. Despite not wanting her around though, he never actually thought about making him get rid of her. So when he finds his kid hiding a kitten in their closet, he has some flash backs to Doomfanger and her irrational hatred of anyone who was not Bamf, and is understandably pissed that his kid has been keeping this from him. He doesn't like the kitten, the kitten doesn't seem to mind him, but he doesn't actually tell his kid to get rid of it despite not wanting it around. The kid can keep the cat as long as they promise to take care of it themself and keep it in their room....It doesn't stay in their room for long and Fell eventually just accepts his fate to be plagued by fluffy things with a penchant for scratching him and then using him as a bed. He just hopes this kitten will help his kid soften up like Bamf's did.
(Swapfell red Papyrus) Rust:
Heh, you're plotting world domination? That's cute. Need your dad to help you build world dominating contraptions for your plans and props for your pranks? He's totally down. Wanna ramble about your plans and how much you don't care about anything? He'll chill with you and listen to whatever you're rambling about now. Need someone to hide behind when one of your ingenious pranks back fires on you? He's not gonna let anyone fuck with his kid, he'll dispense his own consequences if they go too far though. He actually pays a lot of attention to his kid's behavior and tries to engage with them in creative ways, figuring that they're acting out like this because they want attention. He's not gonna let his kid act like a total little shit, but that doesn't mean he's not gonna be laughing in the background when situations call for it.
Rus isn't the type of parent to snoop through his kid's room without a decent reason, but he is really perceptive and bears his kid quietly hushing their kitten's meow in the middle of the night. He's surprised at first to find out that his kid took in a stray, but then he feels pretty proud of them for it. He knew there was a soft spot in them somewhere and now he knows exactly how to nurture it. He'll wait for his kid to bring it up with him before he says anything, but he'll also secretly leave food and treats for the kitten outside his kid's door so that they feel comfortable and ok enough to talk to him about it, knowing that he'll support them.
(Swapfell red Sans) Razz:
Razz butts heads with his kid often, their similar personalities clashing and leaving both of them wishing for the attention and affection that they're missing out on. Honestly though, if his kid wants to act like a villain, then he's going to show them how to do it right. He'll push them to join clubs like the debate team or mock trial, because if they want power then they'll need to either get into law or politics. He won't interfere in any of his kids plans or pranks, but he will watch and then point out ways they can do it better next time. He wants to help them improve and reach their potential, but he's used to being more hands off. He's bad at expressing himself, but he wishes his kid knew that they don't have to try so hard to impress him.
Razz is more than a little upset to find a kitten in his kid's closet. How long has it been here? How come his kid didn't ask him to keep it first? He knows they don't get along well, but do they not trust him? When his kid comes home from school he'll have a conversation about their secret keeping and whether or not they're responsible enough to care for their new pet. If they decide to keep the kitten, it would help the two of them start opening up to each other more, helping them explore and express their feelings after the conversation.
(Swapfell purple Papyrus) Syrup:
Syrup is good at dealing with troubled children, but even he has difficulties with his tiny tyrant. He swears he'll lose his good eye light from rolling it so hard one of these days. He'll play along with his kid's hair brained schemes, plots, evil laughter, and pranks because he thinks it's hilarious to watch other adults get offended, but the whole time he'll subtly be trying to figure out why his kid is acting like they don't give a shit about anything and be thinking of ways to deal with that.
Syrup is actually pretty chill when he finds the kittens in his kid's closet. He's always had a soft spot for strays and castaways. He'll playfully tease his kid about their own soft spot despite their denials, but then he'll also ask them if they want to sign up to volunteer at the local animal shelter. Whether they decide to keep the kittens or not, Syrup realizes how much an emotional support animal could help his kid start dealing with their emotions better and researches how to get them registered for something like that.
(Swapfell purple Sans) Berry:
Berry is the type to sit his kid down and talk to them about their behavior. Why do you want to rule the world? What would you do with it if you did? What are some things that made you think it would be a good idea? He'd start looking closer at his kid's life to see what might need changing or what might be making them so unhappy that they feel like overturning everything. He won't let them pull any pranks that would hurt anyone else, but he finds the evil laughter harmless. He finds it disconcerting that they so vehemently claim not to care about anything. It reminds him of his brother's apathetic behavior and he wonders if he needs to look into therapy for his kid.
When Berry finds the kitten in his kid's closet he realizes that just like his brother having a soft spot for kids, his kid must have a soft spot for animals and not feel very comfortable displaying their softer, kinder side. He'll have a talk with them about trying to keep the kitten a secret from him and then he'll have to decide if his kid is responsible enough to continue taking care of the kitten or not. He agrees to let them keep if if they promise not to hide things like this from him in the future. He wants his kid to feel comfortable and safe enough to come to him with their problems, and he feels like it'll negatively impact them by being punished for coming clean about their issues.