A/N: Okay, before this begins, there are things that need to be said.
Number 1: I don't know if this is going to be a small thing or something I'm going to try and flesh out into an actual story. The reasons for this are a) I like both Homestuck and Persona 5, but I don't know if I can make a good crossover between them. b) I like homestuck in general, but I never fully read the comic, even if I'm making this as if sgrub never happened, and as such I can't say I'll even use the proper terms or personalities for characters, let alone make things or the characters consistent with the comic. Finally c) I am only so good at coming up with things that I don't know if I can make a whole original storyline myself.
Number 2: This is mostly an idea I had in my head that wouldn't go away, and honestly there aren't many Homestuck crossovers outside of maybe on Archive of our Own, and even that is kind of limited at times.
So keep these things in mind. This may be only a few chapters at most, and I don't know how well it'll go, but if someone wants to help or take the idea from me and run with it, let me know.
Chapter 1: The Countdown Begins
Karkat thought he knew what to expect of his life. He would either come to regret everything in his miserable existence as it came to an end, or he would successfully live and become the greatest Threshecutioner ever to grace Alternia. There were little other choices in a society like the one he lived in. It probably didn't help that he really didn't try and figure out a way to keep the knowledge of his secret hidden when the day would come that he could no longer hide it. That was always 'future Karkat's problem'. He also should stop referring to his future self as if he was someone different than himself, and like his future self's problem wasn't his own. Regardless, he saw no alternatives…at least until that night.
Karkat had had a shitty day, which was his normal day. He woke up to an annoying crabdad, his lusus/guardian, screeching up a storm. He argued with it for several minutes before getting on with his day. He re-watched some romance movies, chatted with his hate-friends (at least those who were on and were bearable to talk to most of the time), and a small feelings jam with his morail Gamzee before he got annoyed with him, and finally he relaxed to ease the migraine that was his life. Overall, a normal shitty day. He never thought his life would suddenly take a drastic turn in the span of one night. Or that he would suddenly have such a intense love and hate relationship with the color blue.
Karkat suddenly became aware some time after falling asleep in his recuperacoon that there was a rattling noise like chains. This gave him pause as he had no chains in his hive, before becoming more aware that he was not covered in slime like he was supposed to be. His eyes jolted open and he sat upright in tense paranoia. Taking a small moment to look where he was, he found himself in a small room that seemed to be a cell judging by the barred door. The room was very blue, and he was laying on some (slightly comfy) cushioned board of some sort. There was what looked to be a load gaper as well. He looked at himself and grew very tense. He was in a very ragged uniform with chains wrapped around him, as well as a giant metal sphere attached to his feet. He bolted to his feet.
"What the fuck is with this shit!? Who the fuck did this!?" He asked, mostly to himself. He definitely wasn't expecting an answer to arise.
"He is certainly a more lively guest than we have ever had." Came a strange voice from outside the cell door. Karkat quickly went to the door and looked outside. The room outside his cell was made of stone, and looking in some slight disrepair. Even creepier was the fact that there were certain spots on the floor and walls that had marks on them. RED marks. But the strangest thing was in the middle of the room. There was a desk with a few things sitting on it. Sitting in a chair at the desk was a strange…male being? His limbs were long, as was his sniff nub (the longest Karkat had ever seen, such that he thought it was fake). He had grey coloring on his head, at least what he had on his head. His ocular orbs were wide and bloodshot in a creepy stare, as was his squawk gaper in a giant smile. The being wore a tuxedo of all things, which was offsetting from the room. After what seemed like several minutes, Karkat finally found enough wits to speak.
"Who and what the fuck are you!? Get me out of here you gangly excuse of a hunchback! Why have you grubnapped me!?" He demanded. The being didn't react, sitting there smiling.
"You are right, he is a stark contrast from the other." Said another voice. Karkat looked around, before noticing movement from the side. He looked to his right to see what looked like a young female a couple of sweeps older than a grub. She had the same outer coloring as the male being, but had yellow coloring on her head. She wore a blue outfit and had almost vibrant yellow ocular orbs. She also happened to be holding a giant book in one arm. Karkat slightly wondered if she was slightly stronger than she look holding it as if it was nothing.
"What the fuck is going on!? Who the fuck are you nookstains!?" The male being finally spoke.
"Peace young guest, we will explain if you allow us." Karkat's anger only grew, but he knew he wouldn't get answers if he continued to rage. He took a breath, then calmed himself a little.
"Fine" He said, straining to be calm. "But you better tell me. And get me out of here!"
"I'm afraid we can not." Karkat was about to rage again before the male continued. "Allow me to introduce ourselves. My name is Igor, I am pleased to make your aquaintence."
"And I am Lavenza, assistant to my master here."
"Ok great, whoop-de-fuckin-do. Now why the hell can you not let me out!? Why have you grubnapped me!?" the male, Igor, simply folded his hands in front of his face.
"You are mistaken. We have not…grubnapped you, as you put it." Karkat just was confused.
"This is not your reality. The real you is still asleep in your home…or hive, I believe you call it. You are only experiencing this as a dream." Lavenza explained.
"What…? Are you fucking saying…" Karkat tried wrapping his head around this. "You're saying this isn't real? That I'm going insane?"
"No, my young guest. This is quite real. And very serious." Karkat didn't think this Igor guy would suddenly get that tone of voice, but he felt an apprehension to things now.
"What do you mean real then?"
"Allow me to explain. Firstly, as to why you are in the state you are in, that is due to the room we are in. This is the Velvet Room. The state of this room, is a reflection of the state of your own heart." Karkat was more confused and nervous.
"What the fuck does that mean? What is a heart? Why does anything of mine reflect a dungeon?"
"Ah, do forgive us. Some words for things that you use are different from the ones we use. The heart if the organ that pumps blood to the rest of the body." Karkat's eyes lit up a little.
"Wait, my blood pusher?"
"Indeed. To explain: Deep in your heart, you feel like a prisoner. A prisoner awaiting their execution." Igor said, looking to the side. Karkat followed his gaze before his eyes widened. He hadn't noticed before, but now it was like it was the only thing there. He saw a stump with and axe embedded into it. Next to it was an open container, waiting for something to be put into it. Karkat felt his blood run cold. "You are an outcast, one who doesn't belong, according to the society you live in. The world around you will see your life come to an end when your secret is no longer able to be kept." Karkat was beginning to understand. It still didn't make sense how any of this was happening, but he understood.
"So…what?" he was beginning to get angry again. "You brought me from my body just to tell me all of this!? Remind me my life is limited?" If possible, Igor's smile got wider.
"That leads to the other reason you are here. Tell me, our young guest, what would you say if I told you…that we could help you avoid this fate?" Karkat felt like his word froze. Avoid…his fate? As in avoid getting murdered just because his blood color wasn't supposed to exist? Was that even possible?
"What do you mean?" He asked in an even tone.
"That is the other thing we will explain." Lavenza started. "As you have noticed, we do not look like your people, trolls. Since your people have access to the stars, you will believe when we tell you that we are not from your world." Karkat's ocular orbs lit up. "There is a world called Earth where humans live. Humans look much like we do, and haven't exactly mastered space travel yet, but are advanced enough for it to a minor degree. It is there that we call our home." Igor took up from here.
"Throughout the years, we have come to the aid of humans when certain…phenomena have occurred. Supernatural beings who wished to end or enslave mankind. Through aiding them and the gifts that the unlock, we have guided those who beat these evil beings and kept mankind free to choose their own path. Recently, a young trickster and his team took down a would be god from forcing his will upon the world. However, that is also why we are here." Igor explained gravely.
"The remnants of that would be god escaped our world, floating in an aimless void through space. That is, until recently…" Karkat listened to all of this. He felt like one of the things he could have some pride in is being a leader, and being somewhat tactically smart was required of any leader. He could see where this was going.
"You're saying…this…thing made it to Alternia." Igor nodded.
"Indeed. And with it, came distortion. Quickly, many individuals of your world are being consumed by distorted desires, and pushing those desires onto others. If nothing is done, your world, and others, will be led to ruin." This caused Karkat to become very alerted.
"What!? The fuck to do you mean to ruin?"
"Unfortunately, we do not have the time to explain. The night is starting to wane." Lavenza said somewhat sadly.
"We understand this is confusing for you, as it is strange for us. We know you may think this not real, and may write it off as a dream. You will come to understand in time. For now, we ask you this. Do you have the courage, the will to stand against the world and the coming ruin? You will soon see what we mean, and when you have your answer, we will meet again."
"What!? No you brain dead nook licker! You can't just…not…" Karkat felt his eyes quickly growing heavy as his vision blurred before passing out. Why couldn't anything be easy?