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Senku put his pliers down with force more than necessary, then scratched his head roughly. He wasn't the type to get angry, but he was human after all; it was normal for him to get frustrated.
He was making one of the parts he needed to build a rocket… or that was his plan, but he just failed—again. He could just buy it, but it was really expensive, and he felt guilty asking Byakuya with his meager salary as a teacher.
That was when he got an epiphany: why not make the parts himself? He was already building his own rocket, so making the parts should be no different. But now, after the seventh failed attempt, he was questioning his decision. He had a detailed roadmap, but his hands weren't dexterous, so he kept accidentally breaking them.
Currently he was in the living room because his own room was too small to hold all his stuff. Even the living room was already messy because of him. It was good that Byakuya wasn't the type who cared about tidiness; he had heard from his classmates how often they got told to clean their room.
Today was Sunday, and last he knew, Byakuya was lazing around on the sofa behind him while watching TV. Senku had used it as background noise, so he didn't really know what he was watching.
He glanced at Byakuya and found that his attention wasn't on the TV anymore, but on him. He wasn't sure since when—maybe it happened after he got frustrated. Byakuya raised his eyebrow, silently asking what was wrong. He didn't say it because he knew if Senku needed it, then he would be the one to come to him.
After all those failed attempts, and under Byakuya's thoughtful gaze, he felt he was nearing his limit. He finally gave up and told him what happened, but not the financial reason. Byakuya listened attentively, then closed his eyes and stroked his chin, thinking deeply.
Byakuya suddenly opened his eyes, which glinted as if he had a good idea. "I know! Do you have other things to do today, Senku?"
Senku shook his head. "No, I plan to spend the whole day finishing making these parts."
"Then get changed, we're going out! I'll take you somewhere nice!" Byakuya turned off the TV then walked to his room, but suddenly stopped and turned to Senku. "Oh, and bring all the components needed to make the parts you want." Then he continued to his room, presumably to change his clothes.
Senku had no idea where they were going, but he also went to his own room and followed Byakuya's instructions.
***
Kaseki Craftsman.
That was what was written on the sign above the wooden house in front of him. The place looked shabby—it made him question if it was safe to enter. Unaware of his dilemma, Byakuya cheerfully opened the door and entered. Senku had no choice but to follow him.
"Grandpa Kaseki, are you here?" Byakuya asked, somewhat loudly.
Footsteps could be heard coming from inside, and soon an elderly man appeared. He was short and looked so weak; even Senku could easily beat him in arm wrestling.
"Oho, Byakuya, long time no see. You look as healthy as ever," the old man said.
Byakuya rubbed his neck and laughed sheepishly. "Sorry for not stopping by for a while. I'm glad you also look healthy."
"It's fine, we're all busy." He waved his hand, then noticed Senku's presence and leaned closer to him. "Is he the son you often talk about? He's so big now."
Byakuya patted Senku's head. "Yeah, this is Senku. He is 10 years old."
"Hello, Senku. I'm Kaseki. Nice to meet you."
"Hello." Senku only nodded in turn. Both Byakuya and Kaseki laughed at his crude responses, and he frowned. Byakuya had already said his name and age, so he had nothing else to say. He didn't even understand why Byakuya brought him here.
"So, what's your purpose for coming here today?" Kaseki asked, voicing the same question he had.
"There's something Senku wanted. Go on, Senku, tell him," Byakuya gently pushed his back.
Senku narrowed his eyes. What used to tell it to this frail old man?
He explained what he wanted, and the more he said, the more excited the old man became, until suddenly his clothes literally ripped off, leaving him half-naked and revealing his muscular body.
Senku was shocked, but Byakuya just laughed and muttered, "He really hasn't changed at all." So this is normal?!
"Oho! It's been a while since I heard of such an interesting project! I see you brought all the components too! Wait, I'll bring the tools!" He ran inside, leaving Senku and Byakuya alone. Byakuya sat down on the wooden floor, and Senku sat beside him.
"What's with that old man, Old Man?"
Byakuya was used to his rudeness and didn't reprimand him. "His name is Kaseki. He used to work as an engineer at a prestigious company, but he has now retired and opened his own workshop where he can still make things leisurely. His crafting skills are amazing; he can make anything you ask for, no matter how complicated. I asked for his help when building my own robot."
Senku remembered the robot Byakuya had shown him. At that time he'd been so impressed that he didn't think there were others who helped him.
Kaseki reappeared with a tool box, still half-naked. If he would rip off his clothes every time he got excited, maybe this would be better to save money.
"Let's start building them! Tell me the steps again."
Senku explained again as Kaseki followed his instructions. Senku's initial dull expectation slowly turned to enthusiasm as Kaseki continued to make everything he asked for, all exactly like he wanted. If he didn't know, he would have thought these were all store-bought. Just as Byakuya had said, Kaseki's skills were ten billion percent amazing! Maybe he would ask him to join his rocket-building team, along with Taiju. Age didn't matter after all.
"Heh heh heh." Senku grinned, holding all the finished parts with a gleeful expression. He couldn't wait to go home and used them to continue building his rocket.
After his excitement started to calm down with the completion of the parts he wanted, he was brought back to reality and was surprised that the blue sky had now turned orange. He looked to the side and saw Byakuya was sleeping, his mouth wide open, and he was snoring. Senku snorted, but he felt a little bad; it must have been boring for him just watching them being busy.
Then he noticed there was a fourth person in the room: a boy with black hair, who seemed to be about his age, sitting nearby. His eyes were fixed on the parts Senku was holding.
The boy then noticed Senku staring at him. He smiled, and Senku was unable to look away from those dark blue eyes that looked like a night sky. His heart beat faster than normal.
Kaseki also realized Gen was there. "Oh, Gen, since when are you here?"
Gen now turned his attention to Kaseki. With those dark blue eyes no longer on him, Senku could breathe normally again.
"Well, you seem busy, so I didn't want to disturb you," Gen said. It didn't seem like he was complaining, just stating a fact. "Besides, it's always fun watching you make things, Grandpa. It's like magic." He smiled.
Kaseki beamed. "My grandson is the cutest in the world!" He ruffled Gen's hair, messing up his tidy hair. But Gen didn't mind and even giggled.
After Kaseki stopped his affectionate gesture, Gen smoothed his hair, then turned to Senku again. "This is the first time there is someone my age here. My name is Gen. What's yours?"
His smile made Senku's tongue freeze, but he didn't want to look foolish by remaining silent, so he tried hard to move his mouth. "It's Senku." His response was short again, but just like Byakuya and Kaseki, Gen also didn't seem to mind; his smile remained, in fact, it became wider.
"Nice to meet you, Senku-chan! What are you making here? What are these things for?" Gen pointed to the parts in Senku's hands.
That was a topic he could talk about even in his sleep, so he felt his shoulders relax and quickly explained them. Gen listened and occasionally asked other questions, and their conversation kept flowing—until someone tapped them both on the shoulder, interrupting them.
Byakuya's smile was gentle but also a little troubled. He hadn't realized Byakuya had woken up. "I didn't want to cut off your talk, but it's getting pretty late, and we need to go home. I'm sure Grandpa Kaseki and Gen-kun also wanted to have dinner."
Senku looked outside and saw that the sky had now become dark. Gen didn't seem to notice either, as he now looked embarrassed for not paying attention to his surroundings.
Senku felt a slight ache in his heart. He didn't know why, but he felt reluctant to go home.
It seemed Byakuya could read his mind, as his smile became more encouraging. "We can come again later. I'm sure you still have things you want to ask Grandpa Kaseki, right?"
"Oho, I'll be happy to make anything else you want!" Kaseki said, patting his chest.
"Come again, Senku-chan! With Papa Byakuya too!" Gen said, his face full of happiness. His smile was contagious as Senku mirrored it.
Maybe he would come again, and not to ask for Kaseki's help—although that too, but not just to make something, but also to ask him about something else; something related to Gen.