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Charcoal Rivers @aglobuzzy
Growing Pains


Tanjiro hobbled over to Genya as fast as his legs could carry him. He knelt down. Genya’s breathing was quick and shallow, his brows furrowed in pain.

“What’s going on? Is he okay?” Nezuko asked, joining him.

“I don’t know.”

“Yushiro, go get a blood sample from that demon,” Tamayo instructed. “I need to check up on Genya.”

Tanjiro and Nezuko moved aside from Tamayo to inspect him. She ran a careful claw over his forehead.

“He appears to have a fever,” she said. “The sun will be out soon. Let’s move him inside for now.”

“I got the blood sample,” Yushiro announced.

“Good. Now, inside.”

“Right,” Tanjiro nodded. He got back to his feet and hooked one of Genya’s arms over his shoulder.

“I’ll help, onii-chan.” Nezuko looped the other arm over her shoulder. She grimaced.

“Are you okay?”

“I’m fine,” she said, smiling through the pain. “One of those temari hit my arm. That was after the arrows vanished, so it wasn’t as strong, but I think it might have broken my arm.”

Tanjiro winced in sympathy. “I think I busted a rib.”

“Both of you, inside the cellar,” Yushiro said, jogging down the basement steps. The two siblings followed. “We had this basement constructed as a precaution. It’s designed so that no sunlight can reach it. And there’s enough rooms to house over a dozen patients.”

“It’s wonderful,” Nezuko said. Yushiro smirked in pride. He beckoned for them to follow.

The rooms stretched out from the hallway. They heard scratches coming from one; the man that Muzan turned into a demon right before Tanjiro’s eyes. Yushiro went to the end of the hallway and entered the very last room. Tamayo was waiting for them.

“Here, put him on the bed.” With some effort, the two siblings heaved Genya onto the mattress. “I’ll take a closer look now. You both also have injuries that need attending to. Yushiro, can you take care of them?”

Yushiro didn’t look happy at the prospect.

“Uh, Tamayo-sama, what about the woman from before?” Tanjiro asked. “Shouldn’t we check up on her?”

“I’ll go tell her that the coast is clear,” Yushiro said. “You two, go find a room and wait for me.”

Tanjiro and Nezuko shuffled out of the room and went to the one across from it.

“What do you think is happening with Genya?” Nezuko asked, worry etched on her face.

“I don’t know,” Tanjiro replied, equally worried. “When he ate a demon a few nights ago, he fell asleep for a bit, but he didn’t get a fever.”

They sat in silence. “That temari demon said something about bringing your head directly to Kibutsuji,” Nezuko said. “What was that about?”

Tanjiro shrugged. “I was the one who saw Kibutsuji in the city earlier. Maybe he was trying to cover his tracks. I- I really can’t think of any other reason.”

Nezuko also shrugged. “Could he have recognized you?”

“I don’t think so,” Tanjiro said. “I wasn’t there when our siblings were killed, and none of the others have my red hair.”

That was hard to argue with.

Yushiro and Tamayo came in a few minutes later.

“How’s Genya?” Tanjiro asked.

“He’ll be fine,” Tamayo assured him. “He has a fever, but nothing beyond that. It appears to be a result of him overeating.”


“His body wasn’t prepared for his mass intake of demon flesh,” Tamayo explained. “He is likely to remain unconscious for a few more days, but there shouldn’t be any long term consequences.”

Yushiro nodded. “You can stay here until then, so that your own injuries can start healing, but then you’ll need to leave.”

“We’ll be leaving then, too,” Tamayo said. “Kibutsuji knows of this location now, so it won’t take long for him to send more forces. We have a week, at most.”

Nezuko nodded, understanding. “At least we got the blood of that Demon Moon-”

“It wasn’t a Demon Moon,” Yushiro said with a disappointed shake of the head.

“It wasn’t?”

“No.” Yushiro pointed to his eye. “Demon Moons have their rank carved into their eyeballs. This one didn’t. And she was much weaker than even the weakest Moon would be. If she wasn’t a Demon Moon, likely neither was the other one.”

The two siblings hung their heads in disappointment. “We really thought-”

“You’ll get another chance,” Tamayo said. “Even if they are not Demon Moons, the sample we collected could still be useful. You did well in defeating them.”

Without much other conversation, Tamayo went about patching up their wounds. Tanjiro had a broken rib, and Nezuko had a fractured humerus.

“Total Concentration Breathing can help speed up our natural healing process, but it might be some time before we have another mission,” Tanjiro said as they rested. It was probably daytime, but they didn’t have the chance to check. They fell into a fitful sleep.

When they woke up, they went to check up on Genya. He was still asleep, shivering under a blanket. Tanjiro’s ripped haori and his yukata were draped over a chair. They didn’t even need to check to know that another growth spurt had occurred.

“Poor Genya,” Nezuko murmured, gently stroking his mohawk. Genya mumbled something in his sleep.

“You’re up,” Yushiro’s voice rang out behind them. The demon stood in the doorway. “You probably need to eat. We don’t have much since we’re demons, but there might be something for you in the pantry upstairs.”

“Thanks, Yushiro,” Tanjiro said. They climbed up the stairs, only to find someone else there already.

“You’re… the boy. From last night.” The woman Tamayo had taken in, with her shoulder wrapped in bandages, was fishing for something in the pantry.

Tanjiro nodded stiffly. “How are you feeling?”

“Better than last night.” Even though she said that, her voice sounded heavy.

“We never introduced ourselves,” Nezuko piped up. “I’m Nezuko Kamado, and that’s my older brother Tanjiro.”

“I’m Ariko Yumihiko.”

It was silent for a moment.

“What’s going to happen to my husband?” Ariko asked finally.

“I-” Tanjiro fell silent. “Tamayo-sama and Yushiro-san are going to try to look for a cure. If and and when they make it, your husband will be one of the first to get it.”

“But why won’t he recognize me?” Ariko’s voice wavered. “We’ve been married for almost seven years. He had never hurt me before. Why did those other demons get to act normal while my husband is- like that?”

Tanjiro felt a pang of sympathy. He remembered the turmoil that came from Genya’s initial transformation. Knowing that his big brother was suffering and in pain, but also fearing for his own life.

“One of them is Genya,” Nezuko said. “He’s… our big brother.”

“Is it- is it hard?” Ariko asked. “Knowing someone you love is a monster?”

“He’s not a monster!” Nezuko yelled. “He-”

“It is hard,” Tanjiro said quietly. “It’s hard, because we know how much he hates it. Every second he spends as a demon is a moment of suffering for him. So, we want to get a cure as soon as possible. For him, for your husband, for any demon who might want to change back.”

Ariko looked down. “I’m sorry for what I said. Your brother helped me, and then I spoke ill of him behind his back.”

“Just don’t do it again,” Nezuko said in a warning voice.

“Where is he, anyways?”

“He- got a fever last night. Hasn’t woken up yet.”


“Genya… Genya…”

A singsong voice called out to him. He stayed hidden, though, not wanting the game to end. Hidden in the closet, where no one could find him. He’ll win this game. He and ‘Nemi made a bet that whoever one will get the other’s ohagi.

“Genya…” His mother’s voice again. So sweet, so comforting. He was tempted to run out of the closet and give her a hug.

“Genya… I already found all your siblings… you won… you can come out now…”

Now that she mentioned it, everything had been unnaturally still. None of his siblings had made so much as a peep in a while. Was it really over? Did he win? Could he come out now?

“Genya! Don’t come out! Stay hidden! It’s not safe!”

‘Nemi’s voice. He had never heard his big brother sound so scared.

“Whatever you do, don’t let her find you!”

He felt his chest tighten. It was hard to breathe. He was scared, so scared. He felt something damp dripping down his right cheek, a mixture of tears and blood. He bit down onto his fist to prevent himself from sobbing. His canines felt like fangs.



The closet doors flew open. His mother, with fangs and claws stood before him.

“Found you…”

He skewed his eyes shut and whimpered.



“Nii-chan! Run! Take Rokuta and run!”

He dashed out of the closet and onto the snow filled ground. Everything stung and hurt. Run. Just keep running-

A man with vile veiny red eyes stood before him.


Blood flowed from his mouth and pain pierced his lungs. The man smiled, something malevolent glinting beneath the surface.

“The fact that you are affected by this curse is proof enough that you are a demon. Don’t forget that. Don’t forget what you are!”

“I don’t wanna- I don’t want to-”

Needles stabbed into his body. It felt like his body was on fire. He stumbled back and fell over. A blizzard surrounded him, snow flying by in a flurry.

“I don’t want to be a demon! I don’t want to hurt anyone!”

The wind howled in disapproval.

“Please, someone help! I- I’m scared!”

He felt too small for his too big body. He looked down at his hands and saw claws. When he cried, his tongue caught onto his fangs and bled.

“Please… someone…”

A figure approached him.


He lunged forward and collapsed in his mother’s waiting arms. He felt his body shrink until he was just a small, scared kid again. He screamed and sobbed as she shushed him and stroked his hair. No claws this time. Just his kind, hardworking mother.

“I don’t want to be a demon, Mom,” he sniffled. “I don’t want to kill people. I don’t want to- I don’t want to-”

“I know, I know, Genya,” she said, hugging him closer. “I know it hurts, but I know you’re strong. You’re so strong, Genya. You will overcome this. There are so many people waiting for you to become human again. Promise me you’ll stay strong for them, Genya. Promise.”

He hiccuped and nodded, burying his head into the crook of her neck.

The first thing Genya felt as he opened his eyes were the sheets, twisted up and torn in his claws. He was lying on a bed; an actual bed. The pillow supporting his head was damp with tears. He blinked and sniffled.

“Are you awake?” The blurry figure of a woman entered his vision. Genya couldn’t decipher why, but he felt safe around her.



“I’m sorry, Genya, but I’m not your mom.”

He blinked again. This time, the woman’s features became more clear. Tamayo. That was her name, right?

“Oh…” he mumbled, turning his gaze away. He felt his cheeks flush with embarrassment. He had just called a totally unrelated woman “mom.” “Sorry…”

“No, no, it’s alright,” Tamayo said. Was it just Genya’s imagination, or did her voice waver? “Are you feeling better?”

“I- I don’t know.” Genya pushed himself up into a seated position. He noticed that he wasn’t wearing his purple yukata, instead dressed in off white nightwear. The last thing he remembered was seeing Nezuko slice off the head of the temari demon. And- the dream-

“Did you have a nightmare?”

“I- I don’t know,” Genya repeated uselessly. The dream was already fading from memory, the details slipping away like sand. But, he remembered being afraid. And yet, he wasn’t sure if he could qualify the dream as a nightmare. It certainly wasn’t a good dream, but it wasn’t that bad, either. He remembered warmth and soft reassurances.

“You’re so strong, Genya.”

“What happened?”

“It seems you have overeaten,” Tamayo explained. “Your body wasn’t prepared for the amount of demon flesh you ate, causing you to go into a feverish state. You’ve been asleep for the past two days. While you were asleep, I’ve made some minor adjustments to your body, so that this thing should hopefully not happen again. I’ve also removed Kibutsuji’s curse.”

“So… I can say his name now?”

“Yes, and Kibutsuji will no longer be able to track you. He can sense the location of any demon he creates. However, with the curse gone, he won’t be able to sense you anymore.”

“That’s good,” Genya said with a smile. “I wouldn’t want Tanjiro and Nezuko to get in trouble because of me. Wait- where are they?”

“They are resting in the room across from us,” Tamayo said. “You can go see them.”

Genya jumped to his feet. “Actually-” He stopped short at her voice. “Do you remember what we talked about before the demons attacked?”

Genya slumped. “You need a blood sample from me?”

Tamayo nodded. “Do you want to do it now or later?”

Genya sighed. “Let’s just… get this over with.” He sat back down. Tamayo retrieved a needle and pulled up a chair in front of him.

“Try not to be so tense,” she said as Genya stretched his arm. She gently rolled up his sleeve. Genya whimpered. “I know it’s scary, but it hurts less than it seems.”

“I- I know,” Genya said. “It’s just- when I got turned into a demon- I think something was injected into me. And, so… needles are scary.”

Tamayo offered him a reassuring smile. “I promise this won’t hurt. If it’s easier for you, you can close your eyes.” Genya let his eyes flutter close. “Now, take a deep breath in.”

Genya felt a pinch in his arm. He bit his lip to avoid whimpering. A few moments later, the sensation vanished. He drooped forward, and blinked his eyes open.

“All done,” Tamayo said, settling the syringe aside.  “Sorry for any discomfort.”

Genya glanced to his arm. The injected skin was already healing, a single droplet of blood left behind. He brushed it away with a claw, leaving a smear.

“Thank you for this,” Tamayo said. “I know this is hard for you, but this will definitely help us create a cure.”

“I- I’m happy to help,” Genya said. “I-”  He fell silent again.

“What is it?”

“I- I don’t remember clearly, but I think my mom was turned into a demon. And- I can’t help but wish that she was here… instead of me, even. And you remind me of her, so I really miss her-”

He stopped when he saw tears in Tamayo’s eyes. “Sorry, so sorry-”

The door slammed open. “What did you do to Tamayo-sama?!” Yushiro screeched.

“No, no Yushiro,” she said, wiping the tears away. “It’s fine. Don’t worry, Genya-”

Still, with Yushiro glaring daggers at him, Genya decided it would be better if he left. He backed out of the room, murmuring apologies. He reached the door across from him, and quietly opened it.

“Genya!” Nezuko ran forward and wrapped him in a tight hug, Tanjiro following right behind. “You’re okay!”

“I’m okay, I’m okay,” he said, reaching over to pet them on the heads. “Uh- did you two get smaller?”

“No, you got taller,” Tanjiro said with a smile.

“Last time I measured you was at Urokodaki-san’s cabin, and you were 171 centimeters tall,” Nezuko said. “Now you’re 178 centimeters. I had to mend your yukata again.”

“Sorry,” Genya mumbled. “And sorry for getting your haori all ripped, Tanjiro. But, how are you two doing-”

They were staring as if he had grown a second head. “What?”

“You’re not stuttering anymore!”

“I’m… not?” Genya hadn’t even noticed.

“Tamayo-sama was right!” Nezuko exclaimed. “You are getting stronger with every demon you eat.”

“Just- try not to eat too much,” Tanjiro said. “We don’t want you getting a fever again.”

“You’re so strong, Genya.”

He felt a few tears slip from his eyes. “Genya?”

“I’m okay,” he said, swiping at his eyes. “I- I used to hate being a demon. Really, I still hate it. But, I’ll accept it for now, if it means being strong enough to protect you.”

They hugged again. It felt so warm.

A knock came on the door. Yushiro peeked in. “Your brother is awake, so get ready to leave.”

“Right,” Tanjiro said.

They quickly packed their things, complete with a small share of food for the road. Yushiro and Tamayo also provided them with special knives that had syringe compartments to collect blood samples.

“Just collect the samples, then Chachamaru will bring them to me,” Tamayo said, pointing to her pet cat.

“I’m sorry for making you cry earlier,” Genya told Tamayo under Yushiro’s glare.

“It’s fine,” she assured him. “In fact, it made me… really happy when you said you reminded me of your mom. I’m sure she was a wonderful woman.”

“She really was.”

“Genya, are you ready?” Tanjiro said, opening up the box.


The woman he helped was waiting at the end of the hall.

“Oh, hi-”

“I wanted to thank you for rescuing me,” she said. “Your siblings told me a lot about you.”

“They did?”

She was looking at him without a hint of fear. Genya felt a smile spread over his face.

“We’re going to take your husband with us to keep him safe,” Tamayo told her. “The second the cure is complete, we’ll send you word.”

“Remember the cover story we got for you,” Yushiro said.

“I will,” she said. “Tanjiro, Nezuko, Genya, good luck.”

She climbed out of the cellar.

“We should get going, too,” Nezuko said. “It’s daytime right now, so we need the box.”

“Hang on,” Genya said. “Maybe I can try shrinking now.”

“It might work.”

Genya closed his eyes and tried to will himself to shrink. Maybe it was an instinctual thing, like with the Blood Demon Arts.

“Did it work?”

“Nope, still huge,” Yushiro remarked.

“Oh.” Genya felt his face flush bright red. Great. He just humiliated himself in front of them. With dejection, he crawled back into the box.

“Maybe next time,” Tanjiro said, patting him on the head. Genya grumbled in embarrassment.

“Thank you for everything,” Nezuko said.

“Sure,” Yushiro grumbled. “I guess you’re not an eyesore.”

Tanjiro smiled, closing up the box, and pulling it onto his shoulders. “You ready?”

I shall project me trypanophobia onto Genya and no one can stop me.
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