The monsters in this au are more akin to Kemonomimis, basically they're mostly humans aside from animal parts like ears and tails, why? Cause I prefer it this way for this story.
Long ago, two races ruled over earth:Humans and Monsters.
One day, war broke out between the two races.
After a long battle, the humans were victorious.
They sealed the monsters underground with a magic spell.
Many years later…
MT. EBOTT
201X
Legends say that those who climb the mountain never return…
Princess Junko Enoshima was an oddity among monsters.
If it wasn't because of her dual toned black and white fur, it was her odd behaviors like constantly switching personalities or being strangely cruel and twisted sometimes.
Despite that, she was still a beloved figure in the underground, loved by her parents and monsterkind alike…especially after the disappearance of her older sister Mukuro.
However, due to being royalty, Junko didn't have many friends or people that wanted to get closer to her, everyone of them usually put her in a pedestal because her status and didn't feel like they could get involved with her or didn't want to be close to royalty, plus with being a princess she couldn't met many people on a regular basis either.
And everyone was so…predictable to her, including her parents, she loved them but…yeah.
She was bored, wandering around the ruins, looking at the big hole in the mountain, even if they could climb up they couldn't get out due to the barrier…and even then, none of the monsters were confident of going out and potentially getting thrashed…again, possibly wiped out too.
She wondered though…what humanity was like…
Until she saw something fall down from there…someone actually.
Full of curiosity, she went to check what or who it was…
Junko saw what she assumed to be a human, the first time she saw one…
He…didn't look as scary as she imagined humans were from what she read in the story books, he looked shorter than her. He was wearing a black blazer and pants, a green with red hoodie and red sneakers. He had brown spiky hair with an ahoge. He was laying on the ground trying to get up.
That was a pretty big fall and the only thing he had was slight pain, he was more resistant than she thought.
She got close to him little by little…
Until he looked at her with his green eyes which were red for one second and she backed away.
There was something about them that scared her, they had something in them she couldn't describe…
He looked at her curiosity and blinked a few times before letting out a sigh and focused on getting up and then sitting on the floor, looking up at the hole he fell from.
After being scared by him, Junko slowly got close to him again.
"...Hi" She said to him.
"...Hi?" He said back to her.
"Are you a human?" She asked him.
"...Yes…what are you? Are you actually a monster" He asked her.
"Yup, does it bother you? Does it make you want to fear me? Kill me?"
"No? Why should I?"
The way he asked her, was as if he found the thought genuinely confusing, like something it didn't make any sense at all…
Curious…
"What's your name?"
"...Makoto Naegi…Though I guess now it's just Makoto, though some people and sometimes myself call me Chara"
"My name is Junko Enoshima and welcome to the underground"
"Well, thank you"
"Why did you fall here?"
"I was hiding from a storm, then I saw a hole in the ground and when I went looking, I tripped on a root and fell…You should put something here to cushion the fall, like flowers or something…"
"Why did you climb this mountain's peak? Shouldn't you be home with your parents?"
"...I don't want to talk about it"
Uhh, interesting.
"Well, what ya gonna do now? You can't get out of this place due to the barrier"
"I gotta ask what you meant by barrier…but I…don't really know…"
The way he was talking, it's like he didn't expect to even be alive or he would be stumped even if he didn't fall here…
"Maybe my mom and dad will know what to do, follow me" She said as she got close to him and held out her hand.
He looked at her hand in surprise, like the gesture was unknown to him…did he really never have someone do this for him?
Makoto took her hand so she pulled him up and took her to her parents…
Her parents:Queen Shirokuma and King Kurokuma were surprised about Makoto's appearance, being the first time they saw a human since they were locked underground.
But despite that, they held him no ill will for the actions of the rest of his species a while ago, especially because their fallen star was the opposite of what they experienced a long time ago, he loved monsters and was actually aghast at the treatment they received.
Junko could tell there was something weird when he mentioned the humans, something dark…
But regardless of that, Makoto ended up staying with the king and queen acting as his legal guardians, he got to live with Junko too and they all ended up having a great time, the Enoshima's explained to him all there was to know about the underground and Makoto shared his experiences of the surface and how things changed since last time they were up there. The Monsters even got along with Makoto very well, he began to be seen as the hope for all monsterkind, that they could return and be accepted on the surface again.
Junko for her part was a little apprehensive at first…but eventually grew to appreciate Makoto's presence here, to the point she was glad he took that fall. Because not only she had a new friend at last, but also one she could have fun and never get bored with. Makoto was never predictable, he was always kind and wanted nobody to get in trouble but always did something that she could never see coming. Whenever she pranked him he always managed to turn it around and he was always there to help her and protect her…he was…he was…
He was too good to be true, which is why one day she lost him…
She noticed that Makoto was beginning to act strange at one point…
Well, it was two different behaviors really, she began to notice he would act weird around her, his face would turn red and he would get embarrassed being with her sometimes, though despite that they were closer than ever…
The other one was that he always looked…sad seeing the monsters trapped here, whenever asked he would always say that being trapped under here was something they did not deserve and that he would give anything to fix it.
Junko wouldn't be able to tell, she always lived here and didn't see it as that bad…but then again, she was curious about what the surface was like, it had to be really good if everyone was itching to get back there…with the exception of Makoto, interestingly enough despite is wish to free monsters.
But then the incident that kickstarted the whole destruction of their beautiful life happened.
They decided to make the king a pie for his birthday, having picked up enough from the queen to make at least a decent one.
But they made a dangerous mistake, a nearly fatal mistake…
Instead of putting Cups-in-a-Butter, they put Buttercup flowers.
Her dad nearly died that day, he fell ill and the only thing they could do is feel horrible for their mistake despite everyone else's reassurance it was an accident.
Except Makoto, who laughed…laughed while tears were dropping from his face, the first time she ever saw him cry.
Afterwards Makoto became quiet and saddened from what he did, Junko had no idea of what was going on until he revealed a plan he had been thinking about.
"I'm going to kill myself and you can absorb my soul, then you go to get six more souls and break the barrier and free everyone"
Junko was baffled but intrigued by this plan.
See, Monsters and Humans have certain differences aside from their visual traits, one of them was their souls.
While monster souls create their whole bodies and helped them use magic more easily than a human could, their souls were astronomically weaker than a human soul, to the point they needed the whole underground to equal one human soul, which means a human who can use magic was unstoppable to monsters, even without magic humans had the advantage that monsters were weak to killing intent, if someone wanted to kill them hard enough not only did they dealt lethal damage very easily but also shrugged off their attacks just as easily.
Things like that made the war between humans and monsters a complete slaughterhouse in the humans favor, despite the story they passed down of being an even battle, can't really be justified in their imprisonment of monsters if the war was a massive curbstomp, couldn't they?
But another thing about human and monster souls, was that monsters could absorb them.
The reverse was also true, but monster souls disappeared with them when they died, only boss monster (which was basically her and her parents) souls persisted after death, all human souls persisted after death.
And when a monster absorbed a human soul, they became far more powerful than any human or monster could be, plus they gained the power to cross the barrier.
Monsters could not break or cross the barrier, Makoto could not destroy the barrier even after being taught magic nor could he cross it, their hypothetical fusion could cross it but not break it…
However, the more human souls they got, the stronger they became and with 7 they could become a god, far more powerful than anything in existence…Capable of breaking the barrier and stopping anyone from causing problems if they needed to.
A solid plan if Junko said so herself, a bit surprisingly devious from his part if she said so herself…just a teeny winny itsy little problem…
"Are you fucking stupid!? You will die!"
"Yeah, but the monsters will be free after so long"
"And you dying is worth it!?"
"Yes"
Junko blinked, almost seeming like she was processing the insanity of what she just heard.
"That's…that's fucked up"
"Look Junko, I feel that if I help the monsters go free I can repay them for taking care of me here….and I can make up for poisoning Kurokuma"
"It was my mistake too, you don't see me trying to kill myself over that!"
"Still, I have to help them, I have to free them…"
"And what!? Leave us all alone? Leave me all alone?" Was he really gonna be just like her sister who ran off from her?
"No, because if you absorb me, I will be with you forever, this is why I didn't ask anyone else…because you're the only one I want to do this with"
Junko thought about it, she sure as hell didn't want Makoto to die, freeing the monsters wasn't worth it in her mind the loss of the person she cherished the most…
But she would gain immense power, much more importantly, Makoto would be with her for the rest of their existence together, you couldn't be more united to someone than that…but it meant Makoto would still have to die.
"Come on Junko, we can do this…together…"
…Against her better judgment, Junko accepted…
Maybe if she didn't, everything would have been better…
Makoto chose to depart this world by eating buttercups until he fell deathly ill.
Why didn't he choose a quicker method? Junko did not know, maybe getting something to do it without her parents knowing was hard, maybe he wanted to be poetic in going out the way the man he almost killed, maybe he wanted to control the time of death so she could be prepared to absorb his soul, maybe he was just hardcore.
It doesn't matter, all that matters is that his way to go involved her seeing him wither away slowly while everyone desperately urged him to remain and that they could cure him…
Wasn't Makoto supposed to bring Hope to monsterkind? Cause right now she was suffering like hell because of him…
"This…this is such a godawful plan…" Junko said.
"It's ok Junko, it will work…I know it will"
"It's not about that…seeing you die like this…it's just the worst!"
"Junko, it's fine…I don't mind this at all, it was my idea after all…"
Makoto didn't get it, of course he couldn't, he had so little opinion of himself he didn't see value in his life and found it ok to…throw his life away like this…
And for what? The Monsters? Makoto seemed to think they were completely innocent creatures wronged by the humans, but the truth is they can be just as imperfect as them, it's not worth sacrificing himself like that…
Makoto then held out her hand and weakly smiled at her, in an effort to calm her down.
"Even if I die, I will live within you…and I can't imagine a better existence than that"
…Fuck, why couldn't he be like that before he was dying instead of being shy, it's not fair…
Eventually and despite the efforts of everyone, Makoto passed away, bringing those awful days of watching him slowly dying to a merciful end.
When his red soul emerged from his body, Junko didn't hesitate for a single second and grabbed it, absorbing it into her very being much to the shock of her parents.
Her body suffered a transformation:Being bigger and powerful looking…and speaking of power, she was positively drowning on it!
This was Makoto's power! She was one with him!
"I'm so glad you are, because I'm glad being one with you"
Junko jumped in surprise upon seeing a transparent Makoto in front of her, looking healthier than ever with his eyes glowing red.
"I told you I'll be with you"
She was so happy right now, even if makoto died she will now be one with him forever!
It looked like only she could see him if the non reaction to her parents faces were anything to go by, she grabbed Makoto's body and dashed to the place she found him the first time, they had began growing golden flowers there, she dropped him gently on the flower bed and began floating in the air, easily passing through the barrier until she was in the place Makoto first entered the underground and finally went out to see the sun.
"It's…it's beautiful" She commented.
"Yeah, it's been a while since I saw it, you don't know when something is important to you until it's gone…"
"Yeah…" She said as she basked on it…
"Are you ready?" He asked her
"Yeah…"
It was time to free the monsters…
However, they both committed one fatal mistake, one that thwarted their entire plan and had unseen consequences down the road, consequences that would have made Makoto ditch this whole plan in the first place if he knew them beforehand.
Despite how much he suffered on the surface because of humanity, despite her apathy towards most other people, both of them lacked the will to kill someone.
The humans reacted in terror and anger upon seeing the monster, which made them try to kill her, a combination of fear, the unwillingness to kill and the humans killing intent made her take fatal damage while only fending some off on self defense without killing any.
Makoto, afraid for Junko's life, took control of the body and ran away from there to hopefully get her medical help, his dislike for Humanity increasing to outright hatred from this, next time he certainly will not hesitate.
Junko however was thinking different thoughts.
"Makoto loves me…doesn't he?"
It was something she was certain of, Makoto loved her and she loved him back…so why did this happen? Why was she hurting so much? Why did Makoto hurt her this way? Why was she suffering so much despair?
…Was this how Makoto showed her his love? Was Despair how he expressed his most profound feelings? It has to be…right? Makoto loved her and the monsters but the only thing he brought them was despair.
That has to be it.
Makoto arrived back at the underground and landed right on his corpse in the flower bed, the king and queen watched in horror as both of them gave out, Junko's body fading to dust on top of Makoto's body, the human filled with hatred towards his own kin while the monster believing Despair was the true way to show love.
King Kurokuma was livid from seeing this, both his precious daughter and the human he was taking care of dying right in front of him, in a fit of rage, he declared that any other human that arrives here will be killed and have their soul collected for them to eventually escape, Queen Shirokuma, horrified by her husband's actions, divorced him in a fit of rage and decided to protect any humans from him, abandoning her old position as queen.
Makoto was buried under the bed of flowers he first fell, Junko's body was spread across the flowers and one bear plushie Makoto had in his deathbed as comfort.
Years passed, the monsters managed to collect six souls and one day, the royal doctor Kazuichi injected determination extracted from the souls to a certain plushie for his experiments…
One day, a human fell down.
Hajime got put from the bed of flowers he landed on.
"Stupid hole" He muttered.
"Huh, who are you?"
Hajime panicked upon seeing a transparent human boy glaring at him annoyed.
"...Are you a ghost?" Hajime asked.
The boy snorted. "Yes I am"
Hajime looked spooked.
"Great, now I'm stuck to a human…beats being in a mummified corpse I guess"
Deciding that this was creepy enough, Hajime tried to find a way out.
Makoto was floating near him.
"Can you leave me alone?"
"Believe me, If I could I would get away from you as fast as possible, but we're stuck together"
Hajime couldn't question him more because after crossing a door he encountered something peculiar.
A Plushie.
A living plushie.
"Hello, I'm Monokuma"
And another tale started.
