"My other Father had encountered them before," Silky explained, "I'm not sure how, as I don't receive their memories upon birth, but I do know that he has somehow discovered them previously. That would likely explain as to why he's remaining hidden, because they already know he's a threat and would be targeting him first."

"Demons are real?" Undyne asked.

"Of course," Silky said, "There are creatures born from everywhere. Humans and monsters are born from the world, and creatures like myself are born from the void. Demons, as one would suspect, are born from the underworld. And angels are born from heaven. They serve their purposes just as we do. My Father and I were born to kill, humans and monsters were born to breed and prosper, and demons and angles were born to manage the afterlife."

"Does that mean god is real?" Toriel asked.

"I'm not a priest, but this is more scientific than religious," Silky said, "I know nothing of a god, but I doubt anyone does."

"How is r-religion scientific?" Alphys asked.

"It's simply different layers of reality," Silky said, "As time and space are different layers with the void between them, the afterlife is one of these layers. A layer of existence, where souls are brought to when their physical bodies cannot exist anymore. When their souls have perished, they are dropped down to the layers of afterlife, as they cannot exist in the present layers of reality. From that very bottom layer is where the afterlife resides, accepting souls that drop down. The idea that heaven is in the clouds and hell below is wrong, as they coexist side by side instead of one on top of the other. Father had never been there, but he knew of this. Although one couldn't exactly go around with the knowledge of life after death, as it would likely destroy most people and their beliefs. And it's difficult to get there anyway, as there is a large amount of the void itself to keep people from being able to go down so easily. If there wasn't enough void, souls detached enough from their bodies would simply drop down, so sick people would be dying at a more rapid pace. But if the void gap was too large, than people would still be walking around in rotting bodies."

"The void?" Undyne asked.

"It's e-everything and nothing, j-just a source of power," Alphys said, "I-I saw notes on it before, I d-don't remember who wrote them."

Silky nodded. "It's where my species originated from. The void is incredible in what it does, but there's a reason why people alive don't understand what happens when you die, as the souls disappear from the dimensions. It's impossible to track souls after they die as they travel to the afterlife through all of the dimensions and each layer of the void between them as well, and since the soul isn't connected to the dimensions by a body anymore, we couldn't track it. Impossible to do without connecting it to our dimensions, thus stopping the process and keeping the soul bound to our world. I usually wouldn't tell people about this, not even Sans knew about this, as it could destroy their world views and there is no way to prove it without access to the underworld, but I do believe it is necessary in this situation. Demons were the ones who attacked our home, I do believe their intentions were to collect us and forcefully bring us down to hell. I'm unsure of their reasoning for this, but it would explain why Sans suddenly disappeared. They likely aimed for him first before attacking us."

Papyrus sighed. It had felt like he still just learned what CreepyPasta were before suddenly demons and hell were bring thrown onto him.

Toriel was the one who asked the question plaguing their minds. "So how come Sans was the first target?"

"I've hypothesized some reasons, and there are a few reasonable ones that would make sense," Silky said, "The most logical one is that Sans is our connecter, per say. He was the reason we all came together and could peacefully coexist, he was the link between us. With him out of the picture, you can see how we have all ended up. Seperated, beaten, alone and confused."

The female shifted in her seat, Addy moving to lean against her while holding her hand. It was obvious Addy liked to hug and hold people, judging by how she had held Undyne's hand before, and now was holding onto Silky's. Silky returned the affections by holding her hand back, even rubbing a thumb up her little sisters hand as a way to calm her.

"Another reason would be because Sans is powerful for a monster. He's got quick reflexes, good amounts of magic, and is incredibly tricky and cunning. He would be the first card anyone would aim for if they wanted the CreepyPasta out of the way, as he's not only what keeps us together, but he and Slender are the biggest threats power wise, along with Laughing Jack. All three of which are gone. There was a reason the demons aimed for the three most powerful, and although I may not know the reason, this could be bad."

"What do you mean, Sans is powerful?" Papyrus inquired.

Addy and Silky looked at him with confusion, as if it should have been obvious. But it wasn't, Papyrus didn't understand.

"Uh, he had one H.P," Undyne butted in, "I mean he was smart, but that's like saying Alphys could kill someone. She's smart and I love her, but she cannot exercise for the life of her."

"I-It's true!" Alphys butted in.

"Undyne's right, Sans wasn't the strongest monster when we knew him," Toriel said.

"However, that was 17 years ago, keep in mind," Silky said, "As I said, I don't retain the memories of my parents, but if you believe he wasn't powerful when you knew him, he had a lot of time to grow. As of now, he's certainly one of the strongest of us. One time on thanksgiving, he had fought all of us off while he cooked, he's capable and easily fearsome in battle when he wants to be. He may have been lazy before, as you guys believe, and he still is from time to time, but he was with the CreepyPasta on the run from the police. If he was weak then, there was no doubt he had to grow stronger."

Everyone stayed silent. She was right, it had been over 17 years. That was more than enough time to get some good skills in, and even start a good family. They knew absolutely nothing about him, and it was somewhat frustrating. Papyrus just wanted to be with Sans again.

"Anyway, I believe we have no other choices but to regroup and proceed from there," Silky said, "Which was why I started my search with Addy first. Even if I do find proof that Sans had been taken by demons to hell, there would be no way for me to travel there without forcing death upon myself, a situation that wouldn't be ideal. I apologize for the way we have met, I'm sure coming over for a better introduction in the past would have been the best way to meet your nieces and nephews, but it seems that this is how we had to meet. Thank you for taking care of Addy, it was smart of her to come and find you. I know my father and yourself have had some... negative interactions within your relationships, resulting in us never meeting you, but you have to understood why he disallowed us to meet you."

Papyrus nodded. Yeah, it was all too clear to why Sans wouldn't let his children meet him.

"So, you don't even know for sure if Sans was even taken to hell or not?" Undyne asked, leaning forward.

"Indubitably." Silky ran some fingers through her hair.

"... I don't know what that means," Undyne muttered.

"Uh, w-without doubt, certainly," Alphys said, "Basically she w-was agreeing with you. She had n-no idea where Sans is for s-sure."

"We are unaware if the demon attack was related to Sans' disappearance or not, tracking him or Hewey by their phones have proven pointless. Calling it only emits unusual sounds before it automatically will end the call. Trying to travel through the electronic only results in failure, as if the link suddenly cuts off. It doesn't help that everyone has been split apart, thus making our resources even more limited. It's very fortunate that we managed to find you guys, even though your house is an abomination that deserves to burn. As I mentioned before, we had no backup plans to our house, so once it was discovered we all scattered with no specific residence in mind. If you wouldn't mind, this location would be a good place to recollect everyone, if you wouldn't mind letting serial killers into your house again."

"Again?" Toriel asked.

"I thought that was unspoken with Addy and myself," The tall female said, "We both have killed before, we were raised that way. And no, before you make any judgements, I do have to point out that they simply taught us self defense. They allowed us the free will to kill if we so desired, or to live as normal children. Don't think for a second that just because we're children, that we're automatically innocent and stupid. We were raised by CreepyPasta. Never forget that."

《》《》《》

Okay so I may needa explain a few things.

So basically this is expanding on the whole layers of reality and the void idea. The first dimension is length, the second height, the third depth, the fourth time, and ect. And each layer is separated by some void that sometimes 'juts' through into the layer at connection points, like Sans. But all of these layers are overlapping so basically you get the world we live in where everything has shapes and depth. 

But this is where the religion comes in. Instead of heaven being above earth and hell below it, they both exist side by side in the "0th" dimension, or also called the afterlife dimension. So when humans and monsters die, their souls disconnect from their bodies and 'fall down' into the "0th" dimension. 

Humans live off of determination, so when they die, that means their souls aren't determined enough to stay with their bodies and they go to heaven or hell to be judged and placed accordingly. Basically in order for a person, human and monster, to be alive, their souls have to be connected to the dimensional layers by determination. That's why some people can pull through dangerous situations and still live despite everything, like Frisk surviving the poison or those stories of certain people surviving despite all odds against them. It's the determination keeping their soul bound to the dimensional layers instead of dying and going to the afterlife. 

This is where the resets and ghosts come in. If a human (only humans, since monsters can't be determined, their souls go by magic instead) dies but is still determined, their souls will sort of do a 'last resort' and use the dimensional layers to cling to life. So the souls 'attach' themselves to the first layer as a way to retain their souls on earth, even though their souls are still separate from their bodies. Thus Sally and Ben, as their souls are clinging to life by creating makeshift bodies for themselves due to already having been disconnected from their original bodies. This layer has been dubbed the "1/2th" dimensional layer, right between the first and "0th", because it's still technically dead, but they're still on earth. That's how ghosts manage to live and can't be killed. They're already dead, so killing them again won't do anything because their souls won't pass down to the "0th" dimension, since they're technically "already there" because they already died and were disconnected from the world. 

Then the amount of determination to actually change the dimensions themselves is above any humans on the surface. Frisk could only do it underground because the void was cutting them off, making the amount of dimensional layers and souls to reset smaller. Basically if human souls are determined enough they can become ghosts after death, but if they're more determined they can survive death altogether. And if they have only a small space, they could have enough determination to affect it. But now Frisk doesn't, since they're on the surface.

Monsters are different because they require magic to survive. That's why they dust when they die, because their souls ran out of magic and can't sustain a physical form anymore, thus resulting in dust. So that's why monsters can't become typical ghosts, as they depend on magic. Monster ghosts are monsters that were born as ghosts, like Napstablook. Which means he too has a soul connected to the world, which can be torn away and 'killing him' if he runs out of magic. That's why normal weapons can't kill him, because they won't affect his body and make him deplete magic and hurt him. It's also why, once monster ghosts fuse their souls to something like Glad Dummy did (Mad dummy fused to the dummy in undertale on the geno route and became glad dummy), because that causes their souls to attach to the dummy, a physical item, which in turn can be affected by normal attacks and can kill them. Monsters can also die from old age because their souls become too weak and lose too much magic, disconnecting them. 

Basically how death works overall is that the connection between the soul and the dimensional layers is severed, either by the body being harmed enough, the body ceasing to function, or a loss of determination and magic. 

And also the 1st and afterlife dimensions are separated by more void than the others, because the afterlife doesn't really overlap with the real world. Not to mention the only ways to get down there is either by traveling with an angel or demon through the void, or dying and having your soul disconnect from the real world. It's why Slender and Silky can't go down there even though they can use the void, it acts like the barrier in a sense. Only demon souls and angel souls can go down there, or human/monster souls that have been disconnected from their ties to the real world. Angels and Demons aren't affected in different ways. 

I can't explain anymore because I'll be giving out spoilers, but this has a lot to do with the book. Make sure you read it, and if you're confused, ask questions! I spent a lot of time figuring this out to make sure it works, and I hope combining religion with science somewhat makes sense!

Here's a diagram if u need it. Sorry it's sideways!