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For some unfathomable reason, Eri started calling him ’nii-chan’. When he asked his master about it, Aizawa only said that Eri called everyone in the dorms like that, but both of them knew it wasn’t true. She always put their names before it – even when it came to Mirio, who was her best friend.
Shinsou didn’t know why, but the way she said it and without attaching his name before the title seemed as if she considered him as family. Maybe it was because she was always around whenever they had a training session with Aizawa – the boy wasn’t sure.
Not that he minded it, really. Just like everyone else, he found the little girl endearing and always felt hotness creeping in his cheeks whenever she praised him after a successful training. He didn’t understand how he earned that privilege. He was planning to ask her about it – he only had no idea that an opportunity would happen so suddenly.
If they finished their session late at night, Aizawa always let him stay in one of the spare rooms of the dorm. The incident happened on one of those special nights. He was sitting at his desk, hovering over his homework when he heard a small knock on his door. Shinsou stood up and walked to the door, opening it slightly. When he didn’t see anyone, he narrowed his eyes and was about to close it again when he felt a small tug on his trousers.
”N-nii-chan…” he heard the small sniffling voice and when he looked down two wide and watery ruby eyes looked back at him.
The urge to kill anyone and everyone who made her feel that frightened came within a heartbeat, but the boy held himself back. He didn’t want to scare her more than she already was. Shinsou opened the door, then crouched down so they were on eye-level.
”What happened, Eri-chan?” He asked, brushing some locks of her hair out of her face. He had a good guess. ”Nightmares?” Eri nodded and looked past him in the room.
”Nii-chan, can I-” she started, but then trailed off. Her small hands found their way to his T-shirt, grapping two fistfuls of it.
”Sleepover?” The boy asked and Eri’s eyes lit up like a Christmas tree.
Shinsou pulled her into his room, then picked her up. It made Eri giggle and she wrapped her arms around the older’s neck on instinct. Shinsou walked to the bed, lifted up the comforter and climbed in the bed with the little girl in his arms. Eri’s eyes wondered to the desk where the opened books were still lying, waiting for to be read.
”I am sorry for the inconvenience,” Eri said and Shinsou followed her gaze.
”Don’t worry about it,” he said and ruffled the little girl’s blue locks. ”Not doing homework once in awhile doesn’t hurt anyone.”
”You should take your studies more seriously, nii-chan,” Eri chided him, giving him the lookí. ”You want to get in the hero course after all.”
”You spend too much time with Aizawa-sensei,” Shinsou sighed and the proudness in Eri’s eyes warmed his heart. That girl really loved his teacher. Suddenly a thought popped up in his head. ”Why do you call me ’nii-chan’?”
”Because you are my nii-chan,” Eri declared with a bright smile. When she saw that the other didn’t understand her, she decided to eliberate. ”Daddy likes you. He likes you a lot. Once he said that you are like a son to him. This makes you my nii-chan,” she finished and no, Shinsou’s eyes weren’t stinging.
He hugged Eri to his chest and leaned back down. He pulled the blanket on the top of them while Eri curled into a ball on his chest.
”Thanks, Eri,” he said, kissing her on the top of her head. He didn’t get an answer, tho – the child had been asleep by then.