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Day Six: Quirk Swap

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“What are you doing up?” 

Kyo stopped. “I can’t sleep,” he whined, rubbing his eyes as he clutched Kuma-chan to his chest. He shuffled into the living room and took a seat on the couch next to his father. “It’s hot.” His little body relaxed onto the cool fabric as he cast his father a pathetic pout. 

“It’ll cool off in a few days.” It was unusually hot for September. “That doesn’t explain what you’re doing out of bed.” In five hours, he’d have to get Kyo out of bed to get ready for school. “You have school in a couple hours.” 

“It’s too hot to sleep.”

“You feel okay, brat?” Katsuki placed the back of his hand against his son’s forehead. “Stomachache? Does your head hurt? Your nose running?”


He was definitely warm, but he didn’t have any other symptoms. His teacher had mentioned something about Kyo complaining that he was really warm in the classroom this week, but the weather was quite hot. He and Ochako had made sure to dress him in lightweight shirts and shorts, but he had still been uncomfortable. 

“I’m just hot,” he complained, his little voice sounding too frustrated for a four-year-old. “Why aren’t you in bed?” 

He should be asleep. He had a long shift in the morning. “I was about to go back to sleep.” 

“Did Mama ask for another midnight ice cream sandwich for my baby brother cause he won’t stop floating in her tummy?” Ever since the festival, Kyo insisted that the new baby would be a boy and wouldn’t accept anything that would contradict that statement. 

“No,” Katsuki informed him with a chuckle as he reached for a piece of candy. “Your mom’s asleep.” This time around, pregnancy had turned his wife into a heavy sleeper most nights. “Like you should be.” Like they both should be. 

“Can I watch the rest of the show?” Kyo pleaded, looking at the late night hero review show. 

“Five minutes?” 

“Ten minutes.” Even though his concept of time was still shaky, Kyo knew that ten was more than five. 

Katsuki nodded, “Ten minutes.” He’d make his son go upstairs somewhere in between. 

With a satisfied nod, Kyo reached for a piece of candy to snack on while they watched television. 

“You’re gonna have to brush your teeth.” 

“I already did.” 

“I know.” There was probably still toothpaste splattered on the bathroom mirror from earlier. “But you don’t want your teeth to fall out.” Katsuki placed a hand on top of his son’s head to pull him close. 

“Yeah, but,” Kyo started as he chewed on a piece of candy lace, “aren’t my teeth supposed to fall out so I can get money from the tooth fairy?” 

Katsuki hadn’t planned on them doing the whole tooth fairy thing, but Kyo had lost his first tooth while spending the night at his mother’s house. “Your teeth come out to make space for your bigger teeth. It’s important you brush your teeth so your mouth is healthy.” 

“Okay,” Kyo hummed, nibbling on the candy as his eyes watched the show. “Papa?”


“When will I get a quirk?” His little eyes focused on the hero on the television.

“Soon.” The doctors had told them any day from between the ages of three to five. Kyo was now four, and any indication of a quirk hadn’t shown up yet as far as they could tell. 

“Will I be able to explode things with my hands like you do?”

Weeks before his quirk appeared, Katsuki’s hands were red, raw, and warm to the touch. His mother had mistakenly thought his hands had been stained from paint at school and tried to scrub them clean. Ochako had mentioned the tips of her fingers becoming swollen before her signature figure pads had appeared. 

“Cause this girl in our class just got hers and she doesn’t have the same quirk as her parents.” 

“I don’t either.” Katsuki had been tempted to swipe some of Kyo’s sweat to see if it was flammable like his mother’s. He was nose blind to the smell of glycerin so he couldn’t say if Kyo smelled sweeter. “Mine is a combination from Baba and Jiji. And your Mama doesn’t have the same quirk as her parents.” 

“I know,” Kyo acknowledged with a little whine, “but I wanna be a hero like you.” 

The comment made him smile. 

“And I can’t do that if I can’t make explodes.” Kyo showed his palms to his father.

“Explosions,” Katsuki corrected gently. “And your Mama can’t make explosions, and she’s a hero.” 

Kyo pouted, “But I want to be like you .” 

His son's words made his chest tighten with pride. Katsuki scooted closer to his son and placed am around his shoulders.  “None of your Ojis or Obas can make explosions, and they are heroes.” He couldn't help but wonder what would happen if his son didn’t develop a quirk. Katsuki had been alarmed that one hadn’t appeared yet, even though the doctor wasn’t worried. 

It would serve him right. 

His son would pay his penance for bullying Izuku for being quirkless, while Katsuki would be forced to watch helplessly as his son was ridiculed and bullied. “You can be a hero without being able to make explosions.” 

“Yes, but,” Kyo sighed loudly as he leaned against his father, “your quirk has lots of power.” 

“So does your mother’s.” He could think of several of their friends with powerful quirks, but he wasn’t admitting to anything he didn’t mind Kyo repeating. He really didn’t need Eijirou or Shouto gloating. “If I could trade quirks with anyone, I’d trade quirks with her.” 


“Really,” Katsuki admitted, nodding. “You know your mother has beaten me in fights right?”

“You and mama fight each other?!” 

Fight might not have been the best word. “We’ve had to battle each other. When we were in high school, she beat me in a combat match and she won the whole contest.” 

“No way,” Kyo gasped, looking at his father in disbelief. “I don’t believe you.” 

“You can ask anyone.” He could probably pull up a clip of their fight to prove it. “I’ll see if I can find a video of it. She also beat Shouto.” 

“Mama beat up Oji Sho?!” 

“She didn’t beat him up,” Katsuki chuckled, turning off the television. He closed the snacks and then slapped his hands against his thighs. “She kicked ass though.” 

Kyo giggled. 

“Your mother,” he started, standing up and then picking his son up off the couch, “used her quirk to make the ground shake and crack like an earthquake in their fight.” 

“She did?!”

“She did,” he confirmed. “I can’t do that with my explosions. Your mom can manipulate so many things, so it makes her quirk versatile.” 

Kyo nodded as they headed up the steps. 

“You’d be lucky to have a quirk similar to hers,” Katsuki told him as they walked toward his room. “Or one that’s like your Babas or Jijis.” He sat Kyo on the bed, pulling off his pajama shirt. The little shirt was damp with sweat, and Katsuki couldn’t tell if he was smelling the bubble gum bubble bath or his son’s developing quirk. They’d have to keep an eye on it. 

“Or Ojis and Obas,” Kyo added as he crawled under the covers. 

“I don’t think you’ll get a quirk similar to them.” 

“Maybe Oji Sho.” 

Katsuki did have a cousin who could manipulate and create fire. “We’ll see.” 


Probably not. “We’ll see, brat,” Katsuki repeated as he arranged the covers off of him. “Get some sleep.” 

Kyo frowned, “I didn’t brush my teeth.” 

Shit. “I won’t tell if you won’t,” Katsuki decided as he kissed the crown of his son’s head. “But we’re not gonna let that happen again, right?” 

“I’ll brush them extra good in the morning,” Kyo nodded, closing his eyes. “Night, papa.” 

“Night,” Katsuki responded, slowly exiting the room. Back in his bedroom, he slid under the covers, moving to cuddle against his wife. He buried his nose at the crook of her neck before placing a hand against her stomach. 

“Kyo asleep?” 

Katsuki’s head lifted up at the sound of his wife’s voice. “Why wouldn’t he be?” 

“I figured you all would still be watching movies. You guys typically stay up for another hour or two when you have your midnight movie marathons,” she yawned sleepily as she pushed herself back against him. 

How the hell did she know? “No,” he denied weakly. 

“Yes,” she chuckled. 

“When did you figure it out?” No point in denying it now. 

“Um,” she hummed, “I think when Kyo was about four months.” 

So she knew the entire time. 

“I thought it was weird that Kyo seemed to always sleep through the night,” she told him quietly. “I snuck downstairs and saw you two sleeping in front of the tv. It was really cute.” 

“Tch.” His hold around her tightened a bit as he rested his face in the crook of her neck. “And you didn’t say anything?” He figured the moment she found out, she’d bust them and make them go to bed. 

“It’s nice that you and Kyo have bonding time, even if you’re snacking and staying up too late.” 

“I don’t let him have too much,” he promised. “Plus, we hardly ever do it on school nights.” Only if his work schedule had prevented him from spending a lot of time with Kyo. 

“I know. I don’t care that you guys do it,” Ochako explained. “It’s nice.” 

Katsuki hummed as they lay in the stillness for a moment. “Brat was asking about his quirk.” 



“That’s gonna be interesting.” 

He could hear the smile in her voice. “What if he doesn’t have one?” 

“Then he doesn’t have one.” 

“That shit is gonna be hard for him.” Moments like this he wished he could tell her about his complete history with Izuku. 

How he bullied him for being quirkless. 

How he wouldn’t let him forget that he wouldn’t be able to reach his dream without a quirk. 

How he told him to jump off a building so maybe he’d be born with one in his next life. 

Katsuki knew he could never be completely honest with her about it because he couldn’t reveal the secrets behind Izuku’s quirk. 

There was a very real chance the same things that happened to Izuku would happen to his son if he were quirkless. 

And there wouldn’t be someone there to offer him a quirk to help help achieve his goal. 

“Yeah,” Ochako agreed, “but we’ll get through it if we have to.” 

“I know.” Katsuki hoped they didn’t have to. 

To be Continued...