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Another warm spring sun like any other graced the world that Friday morning. Only, it was no ordinary Friday and shouldn't be treated like some other Friday either.
“Dad! Dad! Wake up!” little Katsuki called, shaking his dad awake.
Aizawa let out a groan, not even opening his eyes. Instead, he rolled over in his futon, his back to his son. "Dad's not at the phone right now. Leave a message. Beep."
“Dad!” Katsuki drawled, shaking Aizawa more. He even climbed over him to reach his face once more. His dad only rolled over again. “Dad!”
Aizawa let out a soft snort, finally rising from the dead. “Alright. I’m up, I’m up.” His smile grew when Katsuki plopped onto his lap with a childish, bright smile. "What's got you so energized so early?"
“Nothing~” Katsuki giddily fibbed. He stared expectantly up at his dad. However, Aizawa only picked him up as he stood.
"Alright, then. Time to get ready, right?"
Katsuki’s smile faltered. “Ye—yeah…”
Aizawa set Katsuki down so he could go through his morning routine. He knew his son already finished his. Katsuki always got ready before him.
Katsuki was speechless when his dad left him. Nothing! Really!? It was a special Friday, and nothing! Well, it was still early. Maybe his dad was still braindead. Yeah, that had to be it. His dad just needed his coffee and breakfast. Right.
With a nod, Katsuki scampered off to the kitchen. He began preparing breakfast and lunch as usual. By the time his dad was finished getting ready, Katsuki was plating their meal.
“Breakfast’s done! Can you get the futons?”
“Already on it.”
It didn’t take long for Aizawa to put away their futons and set up the low table. Another usual everyday occurrence. He then helped Katsuki bring over their breakfast, making himself a cup of hot coffee while he was at it. Straight black to help him through the everyday messes teaching threw at him.
Aizawa was halfway through chugging his first mug when he brought his drink down, finding his son staring back at him hopefully. “What? You want to try it?”
"No," Katsuki answered, going back to his breakfast. He kept sneaking glances up at Aizawa though.
Aizawa raised a brow at this but didn't say anything.
After finishing breakfast, Aizawa went ahead and cleaned up while Katsuki waited by the door. It didn’t take long for Aizawa to finish. Soon, the father-son duo was off to kindergarten. However, on the way there, Katsuki was abnormally quiet.
“Katsuki?” Aizawa started when they were a block or so away from Katsuki’s kindergarten. “What’s wrong? You sick?”
“No…” Katsuki muttered, upset. He turned up to his dad. “Don’t you know what today is?”
“Friday?” Aizawa answered. "It better be. It takes too long for the weekend to come." And even then, Aizawa's weekends tend to be filled with paperwork, be it grading papers or from hero work.
“Friday?” Katsuki repeated. “That’s it?”
Aizawa only shrugged. “Come on. If you’re not sick, then you need to be getting to class.”
Katsuki frowned, pulling away from holding his dad’s hand and running inside. He didn’t even say goodbye. How could he when his own dad forgot his birthday?
Hours later, when kindergarten ended, Katsuki's mood did not pick up from that morning. His sour mood even kept his scared-off classmates from wishing him a happy birthday. So far, it was his worst birthday ever, and he’s only had four other ones. And he only remembered two of the four! In his old life—
Katsuki shook his head. Bitter as he may be, Katsuki would not be looking back at his old life.
“Katsuki,” Katsuki heard, picking up his head. There his dad was, picking him up after school like usual.
Katsuki hesitated a moment before sighing. He trotted up to his dad once building up spirit.
“Have a good day?” Aizawa asked once his son took his hand.
Katsuki didn’t answer his dad. He kept his head down the whole walk to UA. He was still upset his dad forgot his birthday, and it was evident to everyone.
Once they arrived at the 2-A classroom, Katsuki went straight to his usual desk. He kept his head down, not wanting to meet eyes with anybody. Doing so allowed him to miss the worried glances all 19 of his older sibling figures gave him.
“Alright,” Aizawa started, regaining everyone’s attention. “Get into your assigned groups to complete that packet I gave you yesterday. You have until the end of class to finish the rest of them. If you finish beforehand, you can use the time to work quietly on other work or just sit there. Go."
The classroom went and slipped into their five groups. The classroom was louder than usual with everyone talking as they worked together, but it wasn’t anything unbearable.
Katsuki didn't bother paying attention to anything. He pulled out his homework and worked on that. Once they were finished, he pulled out the sketchbook that had been gifted to him in the past. Grabbing his crayons, he drew to pass the time. It was until he was almost finished with his first drawing did someone check in on him.
“Katsuki-kun?”
Katsuki picked up his head, finding his favorite older sibling figure knelt beside him. “Momo-nee-chan.”
Yaoyorozu offered a warm smile. She and her group had finished their classwork. “You okay? You seem beside yourself.”
Katsuki’s eyes dropped to his drawing. It featured kitties in party hats around a cake. “Dad forgot my birthday…”
Yaoyorozu’s heart sunk at Katsuki's soft admission. "Wha—what?”
Katsuki’s lip quivered, but it was clear he tried to mask how upset he was with anger. “Dumb Dad…” He and Yaoyorozu looked up, finding Aizawa in his usual sleeping bag. “He didn’t say anything all morning or when he picked me up with school…”
Yaoyorozu’s heart ached that much more. “That’s awful, Katsuki-kun, but I’m sure it just slipped your dad’s mind. Maybe it didn’t click that today was the actual day of your birthday. Like, he knew when your birthday was, but not that it fell today.”
Katsuki didn’t feel any reassured. “It’s my first birthday since we started living together…”
A third strike to Yaoyorozu's heart, and she was not going to allow any more. “Tell you what, Katsuki-kun,” she started, regaining Katsuki’s innocent gaze. “Why don’t we go out for your birthday after class? I can ask your dad if we can go. While I do that, I can politely remind him what day it is as well?”
Katsuki's eyes brightened a bit. "I wanna go with Momo-nee-chan. But… you don't have to mention my birthday today." His brows furrowed a tad bitterly. "That's Dad's own fault for not remembering…"
Yaoyorozu offered a sympathetic smile. “Okay, I won’t mention it to your dad, and I'll ask the second he wakes up. Or when class ends." Whichever came first. "Would you like to invite anyone else? Kirishima-san? Midoriya-san?”
Katsuki shook his head. “Just Momo-nee.”
"Alright, it's a date then. I'll do everything in my power to make sure you have the best birthday a young, up-and-coming hero like you will ever have."
At Yaoyorozu’s declaration, a hopeful spark shined in Katsuki’s eyes. He finally managed one of his truly bright smiles, making Yaoyorozu’s grow as well.
As the end of class neared, Aizawa awoke from his nap. He stood, signaled to the class to finish their group assignment and turn it in. One person from each group turned in their packet with varying levels of confidence.
Yaoyorozu turned in her group’s packet, taking the chance to ask Aizawa to take Katsuki out for the late afternoon. Once Yaoyorozu asked, Aizawa glanced over at his son a moment. Katsuki's head was down as he packed up his belonging, no doubt trying seem not interested.
Aizawa sighed, giving Yaoyorozu the okay. His student smiled, reassuring him that she wouldn't keep Katsuki out too late and that she won't let anything happen to him. Aizawa didn't doubt her words. She was one of the most reliable students in his class.
Aizawa then offered to pass on cash for any expenses for Katsuki, but Yaoyorozu immediately reassured him it wasn't necessary. This was for Katsuki's birthday, and Yaoyorozu had plenty to happily splurge on her sweet younger brother figure. With that, class ended.
“Alright, Katsuki,” Aizawa called to his son, gaining his attention. “Don’t trouble Yaoyorozu, you hear?”
Katsuki only nodded as he dropped his gaze, pouting.
Aizawa noticed the odd behavior but didn't press. He went on his way as Yaoyorozu went over to Katsuki.
“Shall we head to the dorms first?” Yaoyorozu asked. “We can drop off our book bags, and I can grab some of my other things."
Katsuki nodded once more, hopping out of his seat and taking Yaoyorozu's hand as they headed off with the rest of the class.
“Eh!? You’re taking Katsuki out all for yourself!?” Ashido whined when she and others in the class learned of the outing. “No fair! I wanna go, too!”
“Yeah, same!” Kirishima agreed.
“It’s just for the afternoon,” Yaoyorozu reassured while Katsuki stuck his tongue out. He scooted closer beside her. “We’ll be back before dark.”
"Lucky little brat…" Mineta enviously cried, teary-eyed. "He has Yaoyorozu all to himself and he can’t even appreciate her bod—”
Mineta was unable to finish his crude remark with Katsuki suddenly turning to him, firing an explosion to his face and sending him flying.
“Atta boy!” Hagakure cheered.
“Where you taking the little guy?” Ojiro curiously asked.
Yaoyorozu had to take a moment to think. “Not completely sure yet, but for sure wherever Katsuki-kun would like to go. Anywhere in particular you’d like to visit?”
Katsuki shook his head, keeping his head down.
Yaoyorozu smiled softly once more, holding Katsuki’s hand a little tighter in reassurance.
Right then, the dorm building came into sight. The class all headed in, excited for a free weekend.
Yaoyorozu excused herself to her room while Katsuki waited with the others in the common room. They could all tell he was somewhat down again and did their best to cheer him up. Nothing helped, probably souring his mood even more. Best wait for the Pro Katsuki Whisperer to return.
It didn’t take long for Yaoyorozu to return after changing out of her school uniform and grabbing her purse. The second she arrived in the commons, Katsuki darted straight for her. Pro Katsuki Whisperer, as well as his personal interaction shield.
Yaoyorozu giggled silently. “Shall we go Katsuki-kun? We can grab a small something to eat while we’re out.”
Katsuki nodded. His mood noticeably lightened when he finally got to be with Yaoyorozu again.
With that, the two headed off campus and headed into town. There was plenty to do with nice places to grab a bite, shopping centers to window shop or actually shop, and just a great place to wander during a perfect afternoon.
“Anything you’re hungry for, Katsuki-kun?” Yaoyorozu asked, glad to see Katsuki's mood take a 180. He was looking all over the place with wide-eyed wonder. He hadn't been to this part of town before.
“I—I dunno.” There was so much to take in.
Yaoyorozu smiled with an idea coming to mind. “How about ice cream?”
Katsuki’s head shot back to her. “Before dinner?”
Yaoyorozu giggled. “I’m sure it’ll be alright. Your birthday only happens once a year, right?”
Katsuki smile brightly, nodding his head.
The two hurried off to the perfect place for ice cream. Yaoyorozu took Katsuki to a cute little parlor that specialized in soft-serve ice cream served in fish-shaped taiyaki. Katsuki had strawberry while Yaoyorozu had matcha. Yaoyorozu was sure to take photos of her adorable little brother’s lit up face when their orders came, setting one selfie she took with him with their ice cream as her new phone wallpaper.
After ice cream, the two wandered the shopping center, peeking in many stores. Katsuki was already happy just looking, but when he noticed Yaoyorozu’s reflection on the window of one of the stores, how her eyes sparkled at something inside, he began pulling her in.
Katsuki shooed Yaoyorozu along to look at whatever she was gleaming at before. She was hesitant, the afternoon supposed to be about Katsuki, but the birthday boy reassured her he was happy when she was happy. So, Yaoyorozu grabbed what she was looking at along with a handful of other things in the store. Katsuki happily followed right beside her, repeating over and over again how great his beloved older sister figure would look in everything. Yaoyorozu couldn’t help but pick Katsuki up in the tightest hug, making him erupt in adorable giggles.
Yaoyorozu then went to try on her clothes, reassuring Katsuki that she'd be fast. He had to stay put by the fitting room. Katsuki absolutely followed Yaoyorozu’s instructions. For 10 minutes. Something caught his eye by the kids' section of the store. He looked back at the fitting room. Well, it’d just take a moment.
And a moment later,
“Alright, Katsuki-kun, I’m read—Katsuki-kun?”
“Momo-nee! Look!”
Yaoyorozu turned just as Katsuki reappeared. She wasn't given the chance to comment about Katsuki wandering off when he came back with a little straw sun hat with kitty ears atop.
“It’s just like the one you made me for Christmas, but for when it’s sunny!”
Yaoyorozu did not hesitate to throw that in with her clothes to purchase. Katsuki's birthday present. Along with many other gifts they found the more they wandered about. Toys, art supplies, a full outfit when Katsuki accidentally spilled a bit of his drink on his shirt, books. Lots and lots of books. So many that Katsuki had to tell her to put some back. Yaoyorozu spoiled him all afternoon.
“Momo-nee, this is a lot,” Katsuki said as they were leaving the shopping center with handfuls of bags. A good amount was Yaoyorozu’s, but still. “Are you sure you’re not broke now?”
“Don’t worry, Katsuki-kun,” Yaoyorozu reassured. “It’s your birthday.” Plus, everything she spent that day didn’t even make a dent in her biweekly allowance.
“It’s still a lot…”
“Then think of it as your birthday presents for the last five years! Every year we missed together.”
This got Katsuki’s smiling brightly again. “Thank you! This is the best birthday ever! I love you, Momo-nee!”
It took everything in Yaoyorozu’s power not to cry, super touched. “I’m so glad you’re having a great birthday, Katsuki-kun, but shall we head back now? It’s getting late. Your dad said he’ll pick you up at the dorms.”
And just like that, Katsuki’s smile faltered. He was immediately reminded of his dad forgetting his birthday.
Yaoyorozu noticed, smile dampening a bit as well. "Don't be so hard on your dad, Katsuki-kun. Let’s tell him it’s your birthday when we get back. I’m sure he’ll throw you a huge party and everything afterward."
Katsuki didn’t answer right away. Though, after some thought, he responded, “Okay…”
Yaoyorozu’s smile became full again.
The rest of the trip back, Yaoyorozu was sure to keep Katsuki in high spirits. His mood… wasn’t exactly the same as when they were out, but it wasn’t as bad as during class, so it was something. Besides, she had confidence in Aizawa's ability to be a good dad to Katsuki.
When the two arrived back at the dorms, Katsuki immediately noticed something was up. The lights in the commons were all off. He turned to Yaoyorozu, confused. She only shrugged. Maybe everyone was watching a movie? Maybe the setting sunlight was enough for them to see fine? It was hard for her to say. So, Katsuki shrugged himself, heading in. He failed to spot the growing smile on his sister figure's face as he opened the door and turned on the lights.
Pop! Pop! Pop!
Party clackers went off, confetti clouding the air before falling to the floor. Katsuki stared, shocked by it all—especially by the giant crowd filling the room.
“Surprise! Happy birthday, Katsuki!”
A surprise party. For him. With all his pro hero uncles and aunts, and hero-in-training siblings, everybody—including his dad.
Speechless, Katsuki turned to Yaoyorozu for an explanation. Now he could see her giant smile. "Surprise!" she said. She knew full well about the surprise. Taking Katsuki out wasn’t originally planned, but was great for allowing everyone to set up in the end. “Go on.”
Still unable to manage words, Katsuki stiffly turned back forward. He took one step, but that was all he managed. The rest of his sibling figures already came rushing over to him.
“How’s it feel to be five years old, lil man!?”
“Were you surprised!? You didn’t see it coming, huh!?”
“Katsuki-kun! Open my present first, okay!?”
“No way! Katsuki’s opening mine first!”
“I volunteer to have my present open last. You know what they say, best for last!”
“Excuse you! Mine’s gonna the best!”
“Happy birthday, Kacchan!”
Katsuki still couldn't believe all this was real. He was so in a daze that he didn't even realize he was picked up until the new height allowed him to meet eyes with his dad. Aizawa was staring back at him, smiling. At that moment, tears fell from Katsuki’s eyes. Everyone panicked.
“Katsuki-kun!? Are you alright?” Yaoyorozu worriedly asked, nudging her way forward.
“Oh my god, did I hurt you!?” Kirishima urgently asked, putting Katsuki down. “I’m sorry!”
“Everyone, give Kacchan some space,” Midoriya instructed. Everyone backed off, save for him, Yaoyorozu, and Kirishima. All three were still trying to make sure Katsuki was alright. However, his tears didn’t stop, no matter how much he tried to wipe them away.
The three continued to console Katsuki, only pausing when another came up. They stepped back when Aizawa knelt down to his son.
“Come here.”
Aizawa picked up his son, Katsuki immediately latching onto his neck. When he stood, he gave everyone a nod to reassure them he had everything under control, and stepped out with Katsuki. He was sure to close the door behind him.
“Come on, Katsuki,” Aizawa started. “It’s your birthday. Why the tears? You didn’t think I’d really forget, did you?”
Katsuki didn’t answer, sniffling more.
“It’s okay…”
Aizawa took a seat on the front steps with Katsuki still in his arms on his lap. He let his tears fall, only occasionally helping wipe them away as he held him close.
“I—I thought yo—you did,” Katsuki finally managed to hiccup. “Y—you didn’t say anything al—all morning.”
“I’m sorry. I wanted to surprise you. If I knew you’d be this upset, I wouldn’t have done all that. I wanted you to have the best first birthday with us.”
Katsuki shook his head. “I used to be by myself all the time—even on my birthdays—I’m really happy you’re here now, Dad. Thank you.”
Aizawa smiled, though there was a pang of guilt. So that was why Katsuki was so upset when he thought he'd forgotten. Aizawa knew for sure now he had to be careful when it came to moments like these. Even so, he answered, “I’m glad to hear you love all this. I promise I'll never forget your birthday and we'll have a party every year for however long you want to do them.”
Katsuki’s tears finally began to wane as he looked up at this dad. A sweet smile grew back on his lips
“Better?” Aizawa asked.
Katsuki nodded his head.
“Ready to go back inside?”
Katsuki nodded once more.
With that, Aizawa stood with Katsuki still in his arms. He was prepared to head back inside, but stilled at some familiar hissing and meows. The two turned, finding Katsuki's two stray cats.
“Mitsuki! Masaru!” Katsuki turned back to his dad. “Can they come inside, too!?”
“I don’t see why not,” Aizawa answered. Though, Nedzu might mind, but he couldn’t say no today. So, they went ahead and opened the door for the two cats to stroll in.
Once back inside, everyone surrounded Katsuki once more. When they asked if he was alright, the birthday boy only gave a toothy smile and threw up a peace sign. Katsuki was back to his innocent self.
The rest of the evening was absolutely amazing. There were plenty of Katsuki's favorite foods curtesy of Lunch Rush, and more ice cream plus a giant cake from Satou. When he wasn't stuffing his face with great food, Katsuki was running around with the others. Why Aizawa asked to have Katsuki's birthday at the dorms; it was spacious and everyone was already there.
“Thanks again for letting us have his birthday here,” Aizawa said to Nedzu as he watched his son have fun. Katsuki had the brightest smile he’d ever seen.
“Of course. Anything for Katsuki-kun,” Nezu replied, warily eyeing the two stray cats who were eyeing him back. "I'm glad we could make this day special for the boy. I'm surprised you were able to keep it a secret from him."
Aizawa cracked a soft snort. “Wasn’t easy with how many people were in on the surprise. Mic was the hardest to keep his mouth shut.” He and Nedzu watched as Present Mic joined in on messing around with the kids. “He and Midnight are walking gossip trains.”
“I heard that,” Midnight cut in, walking up to the two. “But… fair… But look at you, being a softy daddy~” She went to poke Aizawa’s cheek, which he immediately swatted away.
“I am not soft. I’m doing what any normal parent would do for their kid’s birthday.”
“Sure, like invite a bunch of pro heroes to spoil him rotten.”
“He considers you all family, so I didn’t have a choice. And spoiled?” Aizawa glanced at the present pile, counting the bags and boxes. There weren’t that many and they weren’t that big—
Wait.
“One, two, three, four…”
19. From his students.
Aizawa threateningly turned to Midnight, glare intensifying when he was met with her sly grin. “What are you all planning?”
Right then, a hearty laugh sounded, followed by the front door swinging open.
“I am here with bags of presents!” All Might announced.
Aizawa immediately turned back to Midnight. She, and all the others, all had grins on their faces. It was Christmas all over again…
Aizawa sighed. “Why couldn’t you give him your gifts normally?”
“Because we knew he’d love this more,” Snipe answered.
And just as the pro heroes believed, Katsuki was hopping with joy as he ran over to All Might.
“Happy birthday, young Katsuki,” All Might said. “To celebrate this glorious day, please enjoy all these gifts from the staff here at UA.”
Katsuki couldn't help but giddily hop in place where he stood. He turned to his dad a moment, showing the excitement in his eyes.
Aizawa couldn’t stay irked with that, giving his son a nod.
Katsuki let out a childish whoop, latching onto All Might in a big hug. “Thank you!” He then went to each uncle and aunt for their own hugs, which they were all dying from. Katsuki was normally never this affectionate with any of the staff—save Recovery Girl maybe—so this was something special for all of them.
“Well, if you ask me, I’d say it’s the perfect time to open all these up!” Present Mic suggested.
"Once Midnight finally lets go, that is," Cementoss added, watching as said pro hero smothered Katsuki with her hug. It was taking Aizawa and Thirteen to try and pry her arms off of Katsuki.
“Hey, hey! Katsuki! Be sure to open the gift from your favorite uncle first!” Present Mic said once Katsuki was free.
“Yeah! Mine!” Ectoplasm said.
Present Mic stumbled, giving Ectoplasm an incredulous look. “Excuse me!?”
“Yeah, lady’s first!” Midnight cut in.
“No, mine!”
“Mine’s bigger!”
“I will fight you!”
Aizawa groaned, pinching the bridge of his nose with his free hand, the other used to carry Katsuki. The staff was worse than his students.
“Everyone!” All Might started, trying to get his coworkers under control. “Please! What sort of example are we giving young Katsuki and our students with this sort of behavior?”
“A bad one,” Aizawa answered, earning more giggles from Katsuki. He then put his son back down. “Go pick something from your hero classmates. Remember, bad behavior does not get rewarded.”
Katsuki let out more giggles as he nodded his head. “‘kay, Dad!”
Katsuki immediately dove into the pile of presents from his 19 siblings, earning their own cheers. They all learned from their teachers, alright. Besides, they got to earn bragging rights if Katsuki picked theirs before another's.
Once Katsuki got through the students' gifts, he finally started going through the staffs'. Not wanting start an uproar since the teachers were more immature than the students apparently, Katsuki blindly chose from their gift pile. Aizawa couldn't help the small well of pride he felt with Katsuki's forward-thinking.
More toys and games, more clothes, and more books, even some toys for playing with his cats came Katsuki's way, along with a few other gifts that stood out compared to the rest, like the higher quality harmonica and drum Present Mic got him. The harmonica Aizawa could handle—Katsuki was getting very good with it—the drum, he was gonna kill his colleague for.
“Aizawa-kun, please,” All Might begged, holding Aizawa back with Cementoss between them and Present Mic. “Not in front of the children on young Katsuki’s birthday. You don’t want to use this day as a mourning day for Present Mic instead of his birthday in the future.”
“And look how happy he is!” Present Mic plead.
“He’s happy with the harmonica.”
“But he’s having fun overall!”
Aizawa turned to the little concert that formed around the couches. Katsuki was in the center of it all, hopping about as he played his new harmonica with Jirou tapping along with his new drum to an upbeat song he learned from one Ghibli film. Everyone had their phones out to record the moment. It calmed Aizawa down, another small smile gracing his face. He could kill Present Mic tomorrow. For now, Aizawa was glad to be in the moment, pulling out his camera to capture Katsuki’s bright face as well. It was a great birthday for little Katsuki—this first of many to come with his family.