[Y/n] grunted as she lifted the jar filled with hot spring water then set it on the ground. She took it upon herself to get hot water for Ruri while Kohaku trained Kinro and Ginro.
[Y/n] stared at her reflection in the water. Her short [h/c] hair that curled under her chin, her doll-like [e/c] eyes, her slightly dirty face.
'You look...so...beautiful...'
[Y/n]'s face turned completely red. Senku's words were still ringing in [Y/n]'s head.
'He's going to be the death of me...' [Y/n] thought then sighed.
She had no idea what to do with these feelings she had, and she refused to admit to herself that she... y'know... had deep feelings for her best friend. [Y/n] shook the unwanted thoughts out of her head and lifted the jar up again, hauling it back to the shed.
"Why are you only making a silver spear?" [Y/n] heard Chrome's voice as she walked closer to him and Senku.
[Y/n] set the jar down.
"Because we need it to get the maximum danger material." Senku explained while showing off the new silver spear.
Ginro instantly fell in love. "Yes! I finally have a silver spear! Thanks, Senku!" Ginro cheered.
[Y/n] stood there a bit confused about what she had to do next while Senku chuckled and packed a bag.
"You don't owe me one millimeter of thanks. I didn't make it for you. Come on, let's get moving." Senku said while slinging the bag over his shoulder, "Ginro, your job is to be the team's bodyguard."
[Y/n] gave a deadpanned look. "Ginro...Our bodyguard?" She muttered as Senku handed her a bag filled with the glass jars that she and Kaseki made, and they were on their way with Ginro cheering 'I'm a bodyguard.'
"I came all prepared because you said it was going to be 'maximum danger'." Chrome said as they pass a hot spring.
"It gets dangerous ahead." Senku groaned while walking behind the group with [Y/n] next to him. Senku noticed Ginro twirling the spear around.
"Ginro, quit messing around and hold your spear forward." Senku warned, and Ginro stopped.
"Huh?" He questioned.
Senku pointed the spear forward. "This silver spear is a sensor. That's what I made it for. Take a good look at the tip." Semku explained, and they looked at the spear, "If the spear turns black...."
"If it turns black...?"
"A few seconds later...you'll be dead." Senku said with a dark look, "You need to get away within 0.1 seconds. We'll all run, too."
And [Y/n]'s eyes widened in fear after connecting the dots.
"The enemy we're about to go up against will send us to the afterlife with just one mistake. This is the greatest hurdle in making sulfa drugs."
[Y/n] gulped. "Sulfuric Acid..." She muttered.
They continued forward with [Y/n]'s fear not letting up.
They came to a river. Chrome and Senku bent over to get a closer look at the water.
"There isn't a single fish in this river." Chrome said.
"I know. Nothing but emerald green liverwort. This is it for sure. Our goal is upstream from here." Senku said and stood up.
"So the greatest hurdle is up ahead..." Kohaku muttered.
"It's okay!" Ginro announced while slowly walk forward, behind them, not taking his eyes off of the spear. "It's okay. It's not black yet." He continued and continued to walks slowly.
"What the hell is the sensor doing walking at the back, Ginro?!" Senku yelled.
"Well, you said I was gonna die! I'm scared!" Ginro yelled with tears in his eyes.
Kohaku sighed. "Want to switch places with me, then? Hand over the silver spear." She said, holding our her hand to take the spear.
"Never! I'll do it! I'll do it, all right?!" Ginro protested, and they continued to walk.
After walking for what seemed like forever, the team finally made it to the pond of Sulfuric Acid.
Ginro's eyes widened. "Chrome, Senku, Kohaku-chan, [Y/n]-chan..." Ginro said while staring at the beautiful pond.
"We're here, Senku." Chrome said while [Y/n] held her trembling hand to her chest. Senku, on the other hand, was out of breath and leaning on a rock.
"I knew it." He groaned while trying to catch his breath, "We've found the source of the materials that were our greatest hurdle."
"I don't even know what we're here to gather, but I can at least appreciate that this is our goal." Kohaku said, looking out into the pond while the others stared in awe, "It's divine and beautiful... An entire spring of emerald, green."
[Y/n] set her bag full of jars down, gently. She still had an uneasy feeling about this place, and she knew that Senku had it too.
"What's wrong, Senku? Is this not our goal?" Chrome asked, and [Y/n] looked at him.
"No, it is. This is perfect. It's the green water we're here to collect. But, the geography bugs me. The poison gases that form here, hydrogen sulfide and sulfur dioxide, are heavier than air. They settle in dips like this one." Senku explained.
"Is that what the silver spear's supposed to warn us about?" Chrome asked.
"Yeah. Silver reacts with hydrogen sulfide and turns black instantly...." Senku said, and [Y/n] noticed Ginro walking closer to the water and his spear began to turn black.
"Ginro!" [Y/n] warned and rushed after him.
"[Y/n]!"
[Y/n] grabbed Ginro by the back of his collar and yanked him back onto the ledge. [Y/n] landed on her butt with Ginro's back against her chest. Ginro began to hallucinate.
"Go away!" He yelled while swinging his arms, and [Y/n] released him.
"Calm down! There's no one there! There's no one there, Ginro!" Kohaku said.
"He's hallucinating." [Y/n] informed and looked out into the water. They witnessed birds falling into the water and completely melt.
"It melted." Kohaku said.
"The bird's wing is melting... What's the deal with this spring's water, Senku, [Y/n]?" Chrome asked.
"It was discovered around the 8th century, in the midst of alchemy research. In our era, it was the chemical that served as the foundation for all kinds of chemical industries... It's called sulfuric acid." [Y/n] explained as she stood up and wiped the sweat from her forehead while Senku was still shaken up by [Y/n] charging into action.
[Y/n] looked down at Ginro, who was still shaken up. In all honesty, she was terrified as well. She wasn't thinking when she charged after Ginro.
[Y/n] placed her hands on her hip and sighed. "I suggest we head back." She said, and Chrome and Kohaku nodded. They packed up their things, and [Y/n] led the way. Senku stared at her as she walked and clutched his fist around the strap on his bag.
Once they made it to the camp, they set their things aside and tried to think of a course of action to take.
"And we can't make the cure-all drug for Ruri without this sulfuric acid stuff?" Chrome asked.
"Nope. We need to secure a source of sulfuric acid anyway, or the chemistry won't develop any further." Senku said, and Kohaku grabbed a bag filled with glass.
"We'll have to push our way through to gather some. I'll risk my life as many times as it takes for Ruri-nee. With my speed..."
"It's impossible." [Y/n] interrupted her in a serious tone, stopping Kohaku, "Back in the modern era, there was a group of researchers that set out to do research around an area of sulfuric acid like this one. The man in front knelt for a moment, possibly to tie his shoelaces..." [Y/n] explained then her and Senku's look turned dark.
"He was dead." Senku finished, "There was hydrogen sulfide at his head's height when he knelt. This is an accident that actually happened. Humans don't stand a chance when Mother Nature wants us dead."
"It makes no difference how fast you are, Kohaku-chan. You will be killed." [Y/n] said, sadly.
"Then what are we supposed to do? I have to save Ruri-nee, no matter what!" Kohaku yelled, and Senku smirked.
"What else? We're going to make gas masks." Senku said, "The only way to fight a chemical enemy is with chemistry."
[Y/n] nodded. She spent the day with Kaseki, making gas masks.
[Y/n] kept herself busy, instead of focusing on the fact that there was no guarantee that they would work.
Senku chuckled while examining the primitive gas masks. "We'll have to see how much poison we can breathe through this. We can't rely on trial and error this time. An error would mean our death."
[Y/n] heard Senku, and her hand clutched around the blueprint.
"All right, next is my mask!" Chrome cheered.
"You won't need one." Senku said.
Later that night, Senku and Chrome went behind the lab to talk, privately while Kohaku and [Y/n] both hid on the tree branch above them, eavesdropping on their conversation.
"Chrome, you aren't coming with us to get sulfuric acid anymore. Stay here." Senku said.
"What? Where's this coming fro-"
"Shut up and listen." Senku ordered, "These gas masks aren't guaranteed to work. Who's going to save Ruri if all the scientists go down."
Chrome looked at the ground.
"All humans die eventually. But knowledge doesn't. It's been passed down for two million years. Listen up, Chrome. I'm going to pass down all the science I know, all two million years of human civilization, to you, right now." Senku continued.
"Wait, wait, hang on! It's too soon! Quit talking like I'm replacing you or something! Jeez, that's so ominous!" Chrome yelled.
"Well, aren't you kind? What are you, my girlfriend? I don't have one millimeter of interest in dying, so relax." Senku mocked, "But the only way to cure Ruri's disease is to charge into the poison gas and get some sulfuric acid. If the three of us do go down together, in that instant, all science will disappear from the face of the Earth."
"So I'm staying behind in case you and [Y/n] die?" Chrome asked, and Senku's eyebrow twitched at the thought of [Y/n] dying.
"Yeah, after I pass down all my knowledge of science." Senku said, and Chrome glared then stepped forward.
"I'm not taking it, if that's the case!" Chrome yelled.
"What are you, a kid?" Senku questioned, "Don't get so fussy about staying home-"
"That's not the point! I have no intention of helping you with a plan that makes it okay for my friends to die!" Chrome yelled, and [Y/n]'s eyes widened, "Sorry to disappoint you, Senku, but I'm not taking your knowledge. So if you, or [Y/n], croak, it's game over for science!"
Chrome punched the tree trunk.
"You're coming back alive, ten billion percent! You have to, Senku! Besides, why are you, the key figure of science, doing the raid through the poison gas? Just use me or someone else. Senku, that's what you would call 'logical.' And yet, you're like, 'Chrome, you're staying at home.' You seem to think you need to protect me. What am I, your kid?" Chrome continued to rant and glared at Senku, "Don't patronize me, asshole."
"My reasoning is logical. I know everything about how gas mask works and about the material we're going to get, so our best bet is for me to go. That's all." Senku said while crossing his arms.
"That's not our best bet! The best bet is for us science users to tag team. We can save each other if it comes to that. Am I wrong?" Chrome asked as Senku looked at him in shock for a moment then Senku smirked.
"When it comes to 'that', we'll already be dead from the poison gas. There's no saving each other." Senku mocked.
"B-But there might be, like, an 'oh, shit, my leg's cramping!' type of situation!" Chrome said, nervously.
"Yeah, you're right." Senku said and placed his hands on his hips, "It might just be just 0.1 percent, but it would raise my chance of survival."
"Taiju and Yuzuriha, was it? They're in the Tsukasa Empire as spies, huh? Aren't they putting their lives on the line? Aren't you and them trusting your lives to each other? If I'm your friend, neither higher nor lower than you, it's not 'I'll protect you.'" Chrome said and held his fist in front of Senku, "That's the wrong line!"
"Damn it, now we have to make another gas mask, thanks to you." Senku said and started to walk away, "Chrome, you can trust me with your life."
"Yeah." Chrome said, "Same to you, Senku."
[Y/n] watched as Senku walked away. "Friends...huh?" She muttered as her expression softened, and she smiled a little. [Y/n] looked over at Kohaku, who was sitting next to her, and saw that she was staring in a daze.
"Chrome, you and I are alike. Everyone would be mighty happy if Ruri-nee were to marry a man like you. But the heavens didn't bless you with the ability to fight. God's not very considerate, is He?" Kohaku questioned then she smiled down at Chrome, "If all goes according to our plan, Ruri-nee will be marrying Kinro or Ginro. If it'd be any consolation, would you want me to be your wife instead?"
[Y/n] gave her a deadpanned look.
Chrome chuckled and turned away. "You're nothing alike. Ruri's ladylike, but you're a gorilla." He said, and Kohaku glared then came down to kick him in the head.
[Y/n] giggled and climbed down from the tree. Once she was on the ground, [Y/n] slipped away, letting the two talk in private.
The next morning, it was time for the next phase in their operation.
"This is the same as when we made Edison's light bulb." Senku said while holding a large glass lens in front of the furnace. "First, we stem-roast some bamboo." Senku held the lens towards the sun, causing the heat from the sun to intensify and roast the bamboo.
"You can use glass in that way, too?" Chrome questioned, and [Y/n] nodded.
"Add potassium carbonate, which can be extracted from ash. We also used this to make ramen." Senku explained, and Kaseki and [Y/n] ground the mixture into a powder.
"That gives us this black powder, activated charcoal, mixed well with potassium carbonate. It'll neutralize and catch the poison gas."
[Y/n] looked and noticed only two gas masks were made. "Two? Shouldn't there be three?" She asked.
Senku put his hand on his hip and the other on the back of his head. "You're not going, [Y/n]." Senku said, and [Y/n]'s eyes widened.
"W-Why not?" [Y/n] asked as she stood up from her seat. Senku turned to her.
"It's a dangerous hurdle, and I don't feel comfortable taking you along." Senku said.
"Senku, we're scientists. This is expected of us. I want to go." [Y/n] said.
"I just want to protect you!" Senku snapped at [Y/n], making her flinch, "Why do you feel the need to protect me?"
Tears filled [Y/n]'s eyes, and Senku's expression saddened. "You've always been there to protect me...even when Tsuaka held me hostage. But, when he attempted to kill you, there was a moment where I didn't know what to do with myself." [Y/n] said as she tried to wipe the tears that were now falling, "My world felt destroyed, and I was lost in this crazy reality. It's not fair to you. I want to protect you, like you do to me; I don't want to be a burden anymore because....because I...I..."
Senku's eyes widened a bit in anticipation, and he felt his heart skip.
[Y/n] wanted to say more, but she couldn't. "I...I care, deeply, about you, Senku. We're best friends and lifelong science partners, after all." She finished, and Kohaku face-palmed.
Senku chuckled. 'Of course. I expected too much.' He thought and patted [Y/n]'s head.
"I don't have one-millimeter interest in dying." Senku said and smiled a little at [Y/n], "You're not a burden in the slightest. Chrome and I will handle this, and we're coming back alive, ten billion percent." Senku said and geared up.
"I'll look after him, I promise." Chrome said to [Y/n] as he walked past her.
"Thank you, Chrome." [Y/n] said.
[Y/n] couldn't bring herself to watch them leave. So, she distracted herself by training with Kohaku and Kinro. But, her fear still would go away.
[Y/n] winced in pain as Kohaku kicked her in the arm. "[Y/n], you have to focus!" Kohaku scolded then stopped and noticed [Y/n]'s trembling hand. Kohaku sighed. "We're done for today." She said, and [Y/n]'s eyes widened.
"N-No, please!" She begged.
"You're trembling, [Y/n]." Kinro said.
"If you can't conquer your fear of people, then you cannot get any stronger." Kohaku said.
[Y/n] held her hands on her chest. "It's not that..." [Y/n] muttered.
"Huh?"
"Yes, I'm scared of people, but that's not what I'm distracted by. I can't seem to take my mind off of Senku. There's no guarantee that the masks will work, and that worries me more. I don't know what to do. If only my mother were here...." [Y/n] ranted with tears threatening to escape, but [Y/n] quickly wiped them away.
"What does your mother do to help you?" Kohaku asked, softly.
"We would sing together. You know, get lost in our own world of music and harmony." [Y/n] said in a gentle tone and looked up at the sky. The sun was now setting. "My mother aspired to be a singer when she got older, but she decided that it was more logical to be a doctor. Her voice...was beautiful."
"Will singing calm you?" Kinro asked, and [Y/n] blushed slightly from embarrassment.
"I've never tried to sing by myself. I'll try." [Y/n] said and took a deep breath then closed her eyes.
Kohaku and Kinro's eyes widened in shock. It was the most beautiful thing they've ever heard.
{A/n: I have no idea what to do with this scene. It's a running joke that y/n sings in every story, so y'all just gonna have to deal.}
~
Meanwhile, with Senku, Chrome, and Ginro, the team finished collecting the sulfuric acid and were hauling it back to the camp until they decided to take a break for Senku's sake. Senku sighed as he set down the huge gear that he was holding.
"We can't break for too long. We're losing daylight." Senku informed.
"Yeah, yeah." Chrome said while sitting down.
"You just want to get back to [Y/n], huh, Senku?" Ginro teased, and Chrome glared slightly at him.
"Shut up." Chrome said.
Suddenly, a warm breeze blow by, making Senku completely relax. He looked up at the orange-colored sky, thinking about what [Y/n] said.
'I...I care, deeply about you, Senku.'
Senku chuckled while Chrome and Ginro looked at him like a madman.
'I care about you, too, [Y/n].' Senku thought to himself and picked the jar up once again.
"You're right, Ginro. I want to get back to [Y/n]." Senku said then his smirk turned evil, "Because we have a lot of work to do. My work is ten billion percent easier with her doing it for me."
Senku started to walk while Ginro and Chrome gathered their things and followed.
"You tried her like a slave." Chrome commented on what Senku said.
"He's in love with her." Ginro whispered to Chrome.
"Definitely in love with her." Chrome whispered back.
"I can hear you." Senku said, causing the two boys to flinch.
Senku chuckled. 'I am completely in love with her.'