This might seems kinda creepy for a while.
Katsuki was three when he first met him.
He was laying in bed, staring at the ceiling, when he saw something in the corner of his eye. He turned, and saw a man. In his doorway was a tall, shadow covered man. The only thing you could see about him, was his eyes; Narrow emeralds with cat-like pupils staring down at Katsuki. The figure moved quickly, and soundlessly towards the child, stopping at his bedside. Katsuki was frozen stiff in freeze. He didnt even have a quirk to defend himself! But strangely, the man knelt beside him in silence.
They stared at each other for a while, before Katsuki heard a hesitant voice in his head.
"...Hello..."
Surprised, Katsuki immediately sat up and clapped his hands over his ears, startling the man.
The figure flinched, blinked, and tilted his head.
"Are you okay?"
Katsuki slowly uncovered his ears and looked in awe.
"Is that your quirk?", Katsuki whispered loudly.
A chuckle.
"You can say things in your head; I'll hear you."
"Is that your quirk?"
The man shook his head. "What is a 'quirk', young one?"
Katsuki pouts. "Don't call me that! My name is Katsuki Bakugou, and dont you forget it!"
The man laughs. "Alright Kacchan. Now, what is a 'quirk'?"
"You get a quirk after you turn four! My quirk is gonna be awesome! More awesome than All Might's!"
The figure leans his head on a shadowy hand. "Who is All Might?"
"The number one hero!"
"Heroes?"
Katsuki tilts his head. "You dont know a lot, do you?"
"Apologies."
Then, they heard footsteps. Katsuki's head snapped towards the door.
"You gotta go! Now!", he whispers.
The man sighs, and stands.
"Goodbye Kacchan."
The footsteps were in front of the door.
"Bye!"
The door opens, and the man disappears with the light.