This one has some dust, not much though. Enjoy!

Pre- timeskip

Ever since Denki got his quirk, he has had strange dreams. Or rather, one singular dream that kept repeating night after night. The dream always happened on a plane of water stretching further than the eye could see(like Tanjiros dream), with stars above and reflecting below him. The person there, a man, was always sitting in the same position, like he was meditating. He had straight black hair that barely reached his shoulders, and a white kimono. Until he was five, Denki quietly watched the man, who never seemed to notice him.

On his fifth birthday, was when Denki decided to approach the man and talk to him. The boy could tell the ravenette was blind, due to the facial scarring and the electrical current that was blocked in his brain (I know this ain't how brains work, but bear with me here).

Even in his dream body, Denki was still covered in wounds. His homelife wasn't the best. But even so, the boy wanted the man to see this beautiful place.

Kagaya Ubuyashiki was meditating, in a trance-like state, when he heard a small voice. 'H-hello?' The voice wasn't spoken in the physical world, Kagaya could tell. Rather, in his head. It sounded like a young boy, and slightly raspy. As if he had been screaming. 'Hello there. And who may you be?' Kagaya responded, in his mind. ' Denki Kaminari.' the young voice replied softly. 'Who are you?'

'Kagaya Ubuyashiki.' The corps master answered, then continued. 'What brings you here?' He asked. There was a pause before the boy spoke again. 'In this mental plane, you are on glass like water. There are bright stars everywhere, further than the eye can see. I-I want to let you look at it.' Kagaya hid his surprise, smiling. 'I would love that.' There was another pause and Kagaya felt a small palm on his forehead, channeling a warm current through his head. Little by little, Kagya began to see his surroundings. The boy's description was accurate, it was a beautiful place, stars surrounding his vision. The man then focused on the boy in front of him- Denki. Kagaya could immediately tell the boy was in bad straits. He was dressed in old, well worn clothes and dirty bandages, scars and dried blood littering his body and clothes. His hair and eyes also stood out. They were bright yellow with black lowlights, his locks spiked and messy.

The duo talked for a while, Denki easily warming up to Kagaya. The corps master could easily tell how affection starved this boy was, and silently vowed to help him whenever possible. Per Kagayas request, Denki talked about his world and its differences, with quirks, hero schools, technology, and so on. Kagaya also described his own world, which was a lot easier, seeing as all he had to do was explain that he lived in the Taisho Period and describe demons. Much to the duos disappointment, Kagaya soon had to pull out of his meditation, sighing slightly as his blindness returned.

As the years passed, Denki and Kagaya met through dreams and meditation. More often than any child should, Denki came with tears and fresh wounds. Kagaya could tell Denki viewed him as a father figure or close uncle, and Kagaya had come to see the boy as one of his own. Though, sadly, they both knew they would never be able to see each other in the flesh

~ Timeskip ~

It was a normal day at U.A. for Denki. His quirk was hurting, it was hard to focus, and he was waiting for battle training so he could let it flow at a steady pace. As he was writing on a piece of paper for class, Denki suddenly felt a demon grasp his throat. 'Shit.' He thought, flipping over the paper and writing frantically:

'A hand just wrapped around my throat. You may not be able to see it, but it's there. It will either kill me or pull me in. I know who this is, but trying to explain would be useless. Give this note to Aizawa and make sure no one tries to take the hand off. It will kill me if someone does. If anyone has dreams of a blind man who seems real, have them ask him where I am. They might be able to answer. There's a strong possibility you'll never be able to see me again, so this might be goodbye.'

Denki passed the note to Mina, who quickly looked over to him, a worried look on her face. Her eyes widened as she saw the hand on his throat, tightly gripping the fragile area. Denki put a finger over his lips and pointed to Aizawa, who was sleeping on the floor at the front of the room. No one else noticed, all focused on their own papers, Mina walking shakily to the front of the room.

Shota woke up to someone shaking his shoulder, cracking his eye open to see Mina with a panicked look on her face. He was about to ask what was wrong, but Mina put a shaky finger over her lips, handing him a note and pointing to Denki. Aizawa quickly read the note, and his head snapped to the electric blonde, only quick enough to see a sad smile on the boy's face, before he was being pulled away. Aizawa dashed over to Kaminaris desk, shouting in frustration and slamming the surface when he was too late. He knew the attempt was futile from the beginning, but this just made it hurt more. "A-Aizawa-sensei! What happened? Wheres Kaminari-kun?" Midoriya asked, Aizawa gritted his teeth. "Kaminari was abducted by villians."

"Blood Demon Art: Leverage." The demon said, his hand passing through a small void. And just as Kyojuro was about to attack, the demon spoke. "I just grabbed the neck on an innocent civilian. If you try to kill me, he'll die! If you stay still, I'll tell you a bit about him." The flame hashira was forced to obey. "This boy I have in my grasp is important to your master. I personally have no idea who he is, and I don't know why or how. But," the demon pulled his arm back, bringing an electric blonde through the vortex, who looked like he was wearing a school uniform, "the boy'll get it if you don't let me go!" Suddenly, before demon or slayer could make another move, the boy let off a blast of electricity, turning the demon to ash and accidentally knocking out the Hashira.

For all who didn't know, Denki knew the hand was a demons' via their unique electrical current. While a humans is natural, Denki recognizing it as 'yellow electricity' , Denki sees a demons 'electricity' closer to 'red'.