It started in China, when a child was born shining like the sun. After that, Quirks began manifesting, both mutative and supernatural in ability. However, no one could miss the fact that, while physical mutation Quirks seemed to be universal, the ones classified as supernatural only manifested in women. Men could sprout horns and tails, but only women could control fire and similar abilities. As such, all men were deemed effectively Quirkless.
Not long later, women slowly began to grow taller and stronger than men. At first there was only a few inches difference, but that difference grew as time passed. Within a hundred years of Quirks manifesting, the average woman was over ten feet tall, while men remained completely unchanged.
It was only after this was the last major change to Humanity discovered. As women grew and Quirks became more prevalent in society, there was a slow decline in the male population. Bit by bit, fewer and fewer men were born. When the decline finally stabilized, men only made up twenty percent of the world population.
Between the manifestation of Quirks, the sudden growth of women and the diminished male population, it seemed like Evolution was intent on leaving men behind...
"Kacchan!" a young boy with curly green hair hollered as he ran towards an equally young boy with spiky blond hair. "Are you going today too?"
"You bet, Izuku!" the blond boy grinned. "I bet we'll be the first boys in history to get Quirks!"
"That would be awesome!" the green-haired boy, Izuku, cheered with stars in his eyes. "Then we could be heroes, just like Lady Might!" The two young boys cheered and danced at the idea until Izuku suddenly began floating up above his friend. "Kacchan! I can fly!" His friend only laughed while a large pair of arms wrapped around Izuku.
"It was just me, honey," Izuku's mother, Inko, smiled as she hugged her diminutive son close. "It's about time to get you checked out." Izuku beamed and hugged his mom back.
"See you later, Kacchan!" Izuku waved as his friend as his mom carried him away. "Mama, do you think I could have a quirk?"
"We'll see," she smiled. "Even if you don't, you're still more special than you think, honey." Giving him a quick kiss on the cheek, she carried her son to the car, to receive his quirk evaluation.
Later that night, Izuku was depressed. He didn't have a quirk, after all. Katsuki might have had a quirk for all he knew, but Izuku was Quirkless, just like every other man on the planet. He just wanted to be a hero with his best friend, but it was looking like that couldn't be a thing.
His mom tried his best to cheer him up, but even after dessert that night he was barely any better. With a heavy heart, young Izuku slowly walked to his bedroom. He was not looking forward to tomorrow morning. Turning off the lights, he slowly crawled into his bed and got comfy.
And that was when he saw the armored man.
Izuku's eyes locked onto them the instant he laid in bed. The person, if they were such a thing, was wearing a complete suit of smooth, dark blue armor, looking like something from a video game. Inside its' helmet, however, there was no face. There were two small flames floating where the eyes should have been. These small flames illuminated the inside of the helmet, showing there was no head inside. With how short they were, they must have been a man. The person stood in front of Izuku's dresser, dead silent, looking right at him.
The man did not react to Izuku's scream of terror, still staring in dead silence. However, his mother did hear him, and in mere seconds he felt the reverberation of her massive footfalls as she ran to his room. She slammed the door open, and yet even at this the man did not react.
"Izuku, what's wrong?" Inko asked with a worried tone as she turned the lights on.
"Th-there's a man standing there, mama!" Izuku cried as he pointed at the still-silent figure. Inko looked in the man's direction for a few seconds before looking back at Izuku.
"Izuku, sweetie, there's no one there."
"Wha...? B-but mama..." Izuku cried again. The man was right there, how could she not see him? Inko looked for a bit longer before her eyes fell on the top of the dresser.
"Hold on," she said as she flipped the lights on and off a few times before turning them back on, giving a soft giggle. "Sweetie, it's just your toys here." She walked to the dresser, passing through the armored man, and moved the Lady Might figures around a bit. "The way they're arranged, the shadow looks like a person."
Izuku was silent as this occurred. His mom couldn't see the man. She couldn't touch the man. The man in question just stood still, looking right at Izuku. Inko gave Izuku a smile, a kiss on the head, and bade him goodnight before quietly walking back out. Izuku was again alone with the man.
"H-hello?" he asked the man.
There was no response.
"A-are you a ghost?"
Still nothing. The man didn't say a thing, didn't react at all. He just stood there,silent and unmoving. With a sigh, Izuku rolled over to go to sleep. Maybe he was just seeing things.
When Izuku woke up, the armored man was not by the dresser. Instead, he was standing by the bed, but not looking at Izuku. He was standing as though he were guarding Izuku, arms folded and watching the door. Izuku again tried talking to him, but was again met with silence. Sighing, he got up and got dressed. To his surprise, the man quietly followed him out of the bedroom. As he walked to the dining room, he noticed the man walked around the chairs.
'Maybe he can touch them?' Izuku thought to himself. 'He can touch things, but things can't touch him...' After a quick breakfast with Inko, he dashed out to meet up with Bakugou. It was Saturday, and they agreed to meet at the park next to the apartments to talk about their quirk assessment exams. He didn't have a quirk, but knowing Bakugou's luck he would. How would Bakugou react to hearing he didn't have a quirk? Izuku could only hope he wouldn't get mad.
"Izu!" he heard Bakugou shout. "Over here!" Izuku turned, still followed by the armored man, and took a few steps before stopping.
Bakugou was running toward him, but he wasn't alone. Running next to him was something...like a dog? It was big, furry and had four legs, but the head was weird. It kinda looked like a dog head, but had four glowing red eyes, and its' teeth looked like chipped stone. Its' fur was black with glowing red underneath, almost like a burning coal. The tail was long and hairy, with a small flame at the end of it. Was it a dog with a fire quirk?
"Hey, Izu," Bakugou smiled. "You doing okay? Do ya got a quirk? Turns out I don't, which sucks."
"M-me either," Izuku said, glancing at the dog from time to time. It just stood there, looking at Izuku.
"So," Bakugou asked, "who's the metal guy next to you? He a babysitter?" Izuku froze.
"Y...You can see him?"
At this question, Bakugou stared in silence for a few moments before pointing at the dog.
"Can you see him?"