Shinso bowed his head in apology as he stood by the living room. "Sorry sensei, Eri, I overslept again." He closed his eyes shut, not believing he'd done it two days in a row now. After the conversation he had with Aizawa-sensei late last night, he'd been up until the early hours of the morning just thinking about it.

"We've been waiting all morning for you!" Eri pouted a bit, holding onto the large wrapped box that Eraserhead got her for Christmas. "It's past noon now!"

Aizawa chuckled at the little girl's annoyance. She had initially wanted to open gifts on Christmas eve, but had been unable to stay up for it.

Shinso apologized a few more times as he watched Eri run towards the tree, grabbing a few gifts from under it.

"Here, Toshi-nii! Hurry, hurry!"

Shinso blinked at the packages in his hand, confused as to why she was handing them to him. "Don't you want to open your gifts yourself?"

Eri looked at him oddly, tilting her head to one side. "Those are yours, Toshi-nii." She pointed towards the scattered toys and torn wrappers on the coffee table. "I opened mine already, except for this one." She raised the huge box she struggled to keep in her arms.

Shinso glanced at the four gifts in his hands, surprised to get some himself. He took a quick look at the cards and realized they were from Aizawa-sensei, Present Mic, Midnight, and… He turned the last gift around in search for a name, but there was nothing. "Who sent this one, sensei?" He saw his mentor's eye twitch at the sight of the unmarked package.

"Fukukado." He answered blankly. "She sent one yesterday for you and Eri."

Shinso narrowed his eyes suspiciously. Why wasn't there a card attached to it?

Aizawa turned his attention back to Eri, helping her clear up some space on the coffee table. He certainly wasn't going to show them what had been written on their cards. He sighed. What the hell was Fukukado thinking, writing a ridiculous claim that they would be spending next Christmas together as a family? He shook his head.

"Toshi-nii!" Eri called out impatiently. "Come on! Come on!" She motioned for him to head over to the couch right next to them.

Shinso eyed the large box on the coffee table as he laid down his gifts right next to it. "Why didn't you open that one, Eri?" He threw her a glance before inspecting the rest of the opened presents scattered on the table.

"This is Shota-san's gift! I was waiting for you so we could open ours together!" She beamed.

Shinso looked at her with wide eyes. He could tell by her disposition that she wanted nothing more than to tear the thing apart and figure out what was inside, but she waited. For him. Because she wanted them to open Aizawa-sensei's presents together. He blinked, feeling a familiar warmth in his chest. "You didn't have to-"

"On three, Toshii-nii!" Eri bounced excitedly on the couch as she looked at him with glee. "One! Two! Three!"

Eri lunched at the huge box, tearing the wrapping paper apart, while Shinso took his time trying to pull out the sticky tapes lodged on the edges.

Aizawa rolled his eyes. "Kid, take a tip from the little girl." He tilted his head towards Eri.

"But it'll make a mess." Shinso looked at him matter-of-factly.

"There are some things you have to do a certain way, because they make things much more fun."

Shinso let out a sigh, tearing through the paper as carefully as he could. He looked at the unlabeled black box in front of him, confused as to what it was. He shook it a few times, bringing it closer to his ear to try and guess what was inside.

Aizawa chuckled to himself as he watched the two of them handle their presents. Eri was diving in nose first, while Shinso was as cautious as ever. He shook his head. They couldn't be more opposite.

"A monster truck!" Eri squealed in excitement as she pulled the box open, jumping up and down before barreling into Eraserhead. "Thank you!"

Aizawa let out a huff of air at the contact, patting the little girl on the head. "You stared at it for a really long time the last time we were at the toy store."

"You noticed?!" Eri blushed, embarrassed at having been caught.

Aizawa nodded his head, before tilting it towards the toy. "Go ahead." He watched her run back to the box, pulling out pieces of the remote controlled vehicle, figuring out how to set it up. Eri was never the type to ask him for things, and was quick to reject any of his offers to buy her stuff, so he made sure to pay attention. He smiled a little to himself, glad that she was better now at accepting things, and was more open with her emotions.

"Sensei… What's this?" Shinso raised a few packets of circle stickers, unsure of what he was looking at exactly. They varied in sizes, but were all transparent and void of color.

"GPS stickers. They activate the moment you take them out of their packaging." Aizawa answered with a small smirk on his face. "The device at the bottom of the box tells you their location at all times. It comes with an app you can add to your gadgets, so you can access information about them as well."

Shinso glanced back at the items in his hand, flattered that Aizawa-sensei had thought of such a gift. It was a perfect thing to have while working out on the field. He could use it to–

"That way you'll finally stop misplacing your stuff."

Shinso blinked once. Twice. "Huh?"

Aizawa jutted his chin at the stickers. "Stick them to your phone, your bag, your tumbler…" He shook his head. "Do you have any idea how many insulated water containers you've lost since we started training?"

Shinso felt his face heat up. Here he thought the GPS stickers were for tracking villains! "I don't lose things that often!" He called out defensively. Sure he's lost more than a dozen tumblers, but that was mainly because he would get so hyper focused around the underground hero and their training. His brain just completely loses sight of anything else.

"Sure…" Aizawa drawled out disbelievingly as he moved off the couch. "You kids go get ready now. We're heading out to eat."

Shinso blinked at this. They weren't cooking together this time? The disappointment he felt surprised him. He hated doing house chores, but there was just something about Aizawa-sensei's house that made it seem… fun.

"I still wanna play…" Eri pleaded, jumping up and down as she pressed her hands together. "Please? Please please please?"

Shinso watched the standoff between the two of them, seeing Aizawa-sensei purse his lips and huff through his nose; no doubt trying to deliberate the whole thing.

"We need to eat first, Eri. When we get back home, you can play with it as much as you want."

"But I waited so long to open it…"

Shinso could see small tears forming in the little girl's eyes as she tried her best to hold them back. He saw Aizawa nod in understanding, before kneeling down to meet her at eye level.

"I know. And it was really nice of you to wait for Hitoshi. But you see, he's just woken up and he hasn't had anything to eat yet."

Shinso watched Eri's eyes widen in understanding. Ruby eyes were on him in the next instant.

"Oh no! We need to go then!" Eri picked up the rest of her toys and started lining them up neatly on the table, taking the torn pieces of wrapping paper in her hand as she headed for the garbage. "Can I leave my toys there first, Shota-san? I promise I'll put them in my room when we get back!"

"Okay." Aizawa nodded, helping her clean up the rest of the mess off the floor. "Toshi, go back to your room and get ready."

Shinso nodded, but was stopped by Eri as she stood in front of him carrying a black trash bag. "Toshi-nii, go ahead and open your presents so I can throw away the paper."

Shinso unwrapped the rest of his gifts, dumping the torn wrappings inside the plastic bag. He got a packet of microfiber towels from Fukukado, an insulated tumbler from Present Mic… He felt his eye twitch knowing for a fact that his mentor probably had a hand at that. The last one was– He hastily stuffed the package inside the pocket of his silk pajamas, quickly announcing his leave as he ran back to his room.

He closed the door, making sure to lock it before heading towards a table to drop the rest of his gifts. He stuffed his hand inside the pocket of his pajamas, pulling out Midnight's Christmas present. He blinked in disbelief. It couldn't be. There was no way that… This was… He couldn't believe it. He held the item in his hands, staring down at it in awe.

A pair of yellow goggles. Just like sensei's.

Knock yourself out, mini-Eraser ;)

He read the small note attached to the eyepiece, before going back to inspect the replica in his hand. It looked exactly like sensei's! He's seen it so many times that it was impossible for him not to distinguish any inconsistencies.

He held it up to eye level, feeling his mind explode at the sheer awesomeness of it all. Holy shit! He was holding onto a pair of Eraserhead goggles! Shit! He's been wanting one since forever, but underground heroes didn't get any merch. There was no way to purchase it.

Shinso slowly pulled it over his eyes, giggling uncontrollably as he ran across the room, pretending to throw imaginary cloth binds all over the place. Just like that, he was eight again, playing hero in his bedroom ecstatic over finding out about the existence of underground heroes – excited over the fact that there was more to being a hero than having insane strength.

Suddenly, he could be one too. Even someone like him… could make it one day.

A few quick knocks on the door made him lose his footing, groaning when his hip landed on the floor.

"Toshi? What are you doing in there?"

"Just a minute!" He called out, panicking at the sound of Aizawa-sensei's voice. He pulled the goggles out of his eyes, stuffing them under his pillow before pulling the door open. He was greeted by a raised brow, and skeptical eyes that scanned his room questioningly.

"Did you need something, sensei?"

Aizawa glanced down at him, noticing his slight discomfort and the way he rubbed a hand against his hip. "What happened to you?"

"I just slipped."

Aizawa let out a noncommittal sound not quite believing his excuse, but decided to let it go. "You have the stickers I gave you?"

Shinso nodded.

"Good. Take one out."

Shinso scrunched his brows in confusion, but followed nonetheless. He went back to his room towards the table, pulling a circular sticker out of a packet before making his way back to the door. "Here."

Aizawa nodded, raising the water tumbler he had in his hand. He smirked when he saw Hitoshi's face turn a bright shade of red. "Stick it on."

Shinso grabbed Present Mic's gift off the underground hero's hand, before slamming the door shut in embarrassment. He didn't realize he forgot to take it with him when he bolted out of the living room.

Aizawa chuckled to himself as he walked away. "Make sure not to lose it this time!" He called out loud enough for his protégé to hear.

Shinso glanced at the family restaurant they were in, surprised to see it so crowded. He and his mother usually celebrated Christmas at home, so he never realized how busy commercial places could get during the holidays.

"Toshi."

Shinso turned towards his mentor, watching him jut his chin towards his plate.

"Finish your vegetables."

He felt his eye twitch at the order, looking down on his plate to glare at the two pieces of broccoli he left lying there.

"You can do it, Toshi-nii!" Eri cheered, stuffing a piece of the green vegetable in her mouth as an example. "They're not that bad."

Aizawa nodded at the little girl, smiling proudly at the action. Eri was never a picky eater, and it made his life so much easier.

Shinso continued to glare at the disgusting plant, not wanting to make a move. It's not that he didn't like vegetables. He just hated this particular one.

"You won't get dessert unless you finish it."

Shinso raised a brow at this. "Fine with me."

Aizawa hummed at this, crossing his arms on his chest as he leaned back against the booth they were situated in. "Alright. Then no one gets dessert unless all plates are cleared."

Eri's gasp was instant. "Toshi-nii…"

Shinso felt himself slowly drowning in guilt at the sight of the little girl's wide pleading eyes.

"Can I help him, Shota-san?"

Aizawa shook his head. "Sorry, Eri. That's his responsibility." He smirked at the glare his protégé sent him, amused by his resistance. The kid was willing to jump off a building with only his cloth binds to protect him from the fall, but wasn't willing to stuff a tiny green leaf in his mouth? He chuckled.

Shinso felt his annoyance grow at the sight of the amused older man. He knew exactly what the underground hero was doing. He used him earlier to get Eri out of the house, and now he was using her to get him to do his bidding as well.

"Toshi-nii…"

He was met with the little girl's doe eyes once again. This time she also had her hands up in a prayer towards him. He sighed in resignation. He stabbed each piece and stuffed them both quickly in his mouth. He held his breath and chewed as fast as he could, washing it down with a generous amount of grape juice.

"Yehey! Congratulations, Toshi-nii!"

"See? That wasn't so hard." Aizawa grinned when the younger boy glared at him once again as he grumbled under his breath. He shook his head in amusement, excusing himself so he could head to the restroom.

Shinso sighed out loud the moment the UA professor left the table. He could still taste the broccoli in his mouth, making him take another sip from his juice. Suddenly, he missed his dining table at home. There, no one would force him to eat anything he didn't want. He always ate alone after all. He blinked, recalling the previous day full of laughter in Aizawa-sensei's kitchen. He glanced down on his plate, seeing a few bits of broccoli left on it. Well… Perhaps they weren't so bad after all.

"Excuse me– Oh, where did your dad go?"

Shinso looked up at the waitress holding onto a black clipboard with a receipt snapped on it. "Uh…" Should he correct that statement? Aizawa-sensei was a lot of things to him – his professor, his mentor, his idol – but he wasn't his father. Even though people always assumed he was. Even though Eraserhead never bothered to deny it. Even though deep down, Shinso really wanted–

"Should I just comeback? Or is your dad on his way?"

Shinso snapped out of his thoughts. "Uh, you can just leave it with me." He pulled out his wallet, sifting through it to grab a credit card when a hand landed on his shoulder.

"Don't even think about it, kid."

Shinso froze in place. Did Aizawa-sensei hear their conversation? Did he notice that he didn't deny it when the waitress…? He swallowed the awkwardness down his throat, wishing the underground hero hadn't heard a thing.

"Did he ask for the bill?"

"Uh, no sir. I've just been told your table was checking out?"

"No, we weren't."

"Oh dear! My deepest apologies, sir. I didn't mean to hand the bill to your son. There must have been a mix up!"

"It's fine."

Shinso blinked at the exchange, realizing Aizawa-sensei hadn't bothered to correct the lady either. The warmth in his chest was back with a vengeance. So much so that he had to tell himself a hundred times that it was because it would be too troublesome to explain why an adult man was out with two kids who weren't his.

He watched Aizawa sensei pay for the bill, helping Eri down from the couch as they made their way out of the family restaurant. Shinso remembered feeling the biting cold the moment they stepped out of the house earlier; but now, as they stalked through the snow-covered streets, he was filled with a warmth he couldn't quite explain.

"Taiyaki!" Eri exclaimed, pointing towards a stall near the park.

"Do you want one?" Aizawa asked, sensing the little girl start to catch herself. "We haven't had dessert yet."

"Uh, it's okay, Shota-san! We just ate after all."

Aizawa sighed, bending down on one knee to look her in the eye.

"Eri. What did I say you could do when you want something?"

Eri looked down towards her shoes, fidgeting with her hands as she chanced a glance at Eraserhead every now and then. "Ask." She answered quietly.

"Good. Now show me. How do you ask me for Taiyaki?"

"It's really okay, Shota-san. I'm-" Eri paused at the look of encouragement her guardian sent her way. She took a deep breath in, strengthening her resolve as she nodded. "May I please get Taiyaki?"

Aizawa smiled, placing a hand over her head in approval. "Yes, you may. Go ask Toshi if he wants some."

Shinso blinked at the exchange. They were now, more than ever, every bit the father and daughter duo. He nodded wordlessly at Eri's inquiry, walking with her towards the food stand. She asked them both what they wanted, before ordering for all three of them.

"Must be tough being such a young dad, huh?"

Shinso blinked at the statement, turning to eye the elderly couple manning the Taiyaki stall.

"And with two children at that!" The old woman beamed at Eri, waving at her from behind the kiosk.

"It has its moments."

Shinso forgot to breathe. Did Aizawa-sensei just…?

"Oh my, what a doting father we have here!" The old woman chuckled. "Reminds me of someone I know…" She turned her gaze towards her husband, whose face seemed to have turned a few shades of red.

"I don't spoil our kids!"

"Sure…"

"I can be quite the disciplinarian you know!"

"Of course, dear. I don't doubt it for a second."

The rest of the old couple's squabbling went over Shinso's head. The only thing that kept playing in his mind was the thought that not only did Aizawa-sensei not deny their claims, but he even… acknowledged them.

"Here you go."

Shinso blinked at the Taiyaki in front of him, reaching out for it when the old man nudged it towards him one more time. He moved to take his wallet out of his back pocket when a hand landed on his head.

"Just be a kid and let the adults pay."

Shinso felt himself bristle at the statement. "I'm sixteen. I'm not a kid anymore."

Aizawa ruffled his hand against his protégé's hair before taking out his wallet. "You'll always be a kid to me."

Shinso looked down at the Taiyaki in his hand, not knowing what to respond to that.

"Oh my, what a responsible son you have! Paying for his own meal!"

"Sixteen, huh? That's a pretty difficult age."

Aizawa hummed at the old man's statement. "He's entering his rebellious phase."

Shinso didn't know if he wanted to melt all the way to the floor, or explode into a million pieces. "I'm not rebellious!"

Aizawa ignored him, continuing to address the elder couple. "Earlier, we had a standoff over vegetables. He's sixteen and he still doesn't eat them."

Shinso saw the small smirk his mentor threw him, no doubt taking a piss at him by playing along with the older couple. He was sure Aizawa-sensei was just messing with him, but he had no idea just how much this whole thing meant to him.

"You take good care of your dad now, alright kid?"

"Don't give him such a hard time! You're the eldest so you have to watch out for your sister."

It took Shinso a few moments to realize that he was the one being addressed. Unable to find his voice, he opted to nod at the older couple, before walking away. It was a chilly Christmas day, but the steaming Taiyaki in his hand, and the burst of affection in his chest were enough to keep him warm even in the coldest December night.

"You have everything?"

"Yes, sensei."

"Your clothes all in there? Your plane ticket?"

"I have them."

"Your gadgets all charged? Passport? Cash?"

"Double checked and ready."

"Your water tumbler?"

Shinso felt his eye twitch as his mentor grinned down on him. "I have it." He replied through gritted teeth.

Aizawa chuckled at his protégé's expression, no doubt annoyed at having been reminded of his tendency to lose his things.

"Bye bye, Toshi-nii…" Eri called out weakly as she leaned against one of Eraserhead's legs. It was two in the morning, but she was doing everything she could to stay awake.

Shinso bent down to pat her on the head. "You didn't have to stay awake."

"But I want to see you off…" She replied with a yawn, rubbing at her eyes to try and keep them open for as long as she could.

Aizawa chuckled at the sleepy little girl, bending down to pull her up against his chest. Her head was on his shoulder as she hooked her arms around his neck.

"She told me to wake her up before you left." Aizawa tapped her back a few times, willing her to sleep. "She made me promise."

Shinso nodded at this, smiling at the sleeping little girl, when the headlights of an approaching vehicle made him turn around.

"Your ride's here." Aizawa jutted his chin towards the parked taxi, waving at the driver who peeked at them from an open window.

"Yeah." Shinso nodded at the driver curtly, turning back towards the father and daughter pair in front of him. "Thank you so much for everything, sensei. This Christmas has been…" The best I've ever had, he stopped himself from saying. "Fun." He settled on instead. "I had a lot of fun, sensei."

Aizawa's eyes widened at the statement, smiling a bit when he realized the younger boy really meant it. Hitoshi was always so focused, so serious, and so driven by his goals. It always made Aizawa wonder if the kid was ever really enjoying the journey. He wanted him to have fun. He wanted him to laugh, and be silly, and do crazy shit that people his age should be doing.

He wanted him to just be a kid.

"Take good care of yourself, sensei."

"You take care, too." Aizawa reached a hand out, dropping it onto his protégé's head. "See you next year, kid."

It was just five words, but those five words meant the world to Shinso. Those five words told him 'You're always welcome', 'You have a home here', 'You have someone to come back to'…

'I'll still be here.'

Shinso made his way to the taxi, turning around one last time to nod at his mentor. Maybe it was the darkness of the night, or the growing chill in the air. Maybe it was the impending goodbye, or the sentimentality of the holiday season… But for once, he just wanted to be honest with himself. He wanted to acknowledge something he's long since known, but had always been afraid to say out loud.

But now, as he stood by the door of the car, watching Aizawa-sensei smile at him softly, he felt like he could finally admit it. He knew he was out of earshot, but it didn't matter. He was here to hear it for himself. He smiled.

"I'll see you next year, dad."

End of story!

And it's finally finished T.T

What started as a short three-shot had turned into this anything goes nine-chapter story that has me in the feels. I love Shinso and Aizawa so much and I always look forward to their interactions in the manga. With the next anime season coming up, I can't help but get hyped! We'll finally get Shinson and Dadzawa moments in 3D!

If you're a fan of Haikyuu, do check out my finished ensemble story! If you liked this, I'm sure you'll love that too ^^

Thank you so much for reading :) I hope this inspires more people to write about their wonderful father and son relationship!

A review would be very much appreciated! Please stay safe everyone, and until next time ^^