Place song when they mention humming the second time, enjoy!:

After their long walk back from the cave they got home safely. She decided to make a few pots as Senku burned the swallows in the fire place. He held it with two sticks as he intently stared at it.

Taiga stayed closed to him as she worked on the second pot of the day.

He was on his second too. He had done that experiment before, but he wanted to do a second test of all of his past experiments. Both trials failed at the end, getting to the same conclusion he had.

They decided to make it their day and go to bed.

Their night routine took over, and Senku slept next to her as she wrote things in his back, tears rolling off her cheeks. Humming a song in her mind in hopes to get it off thinking.

In the morning, Senku stared at Taiga scratch her upper chest as the grass dress poked her more since the grass had become yellow and had various ends loose from the hunt she did with the deer. It simply looked uncomfortable. Especially when she bent.

"Here" he handed her his coat.

She stared at him in confusion.

"Wear it. You can give it back once you finish making your clothing." He said as he stared at the scratches the grass made.

"Thank you" she murmured still concern, but she then smiled in appreciation. She was glad she was off her period, she wouldn't want his coat to get stain by it. The black shorts wouldn't have been enough to contain the blood through if she had it.

She took off the dress and wore it as she hid behind the trees as Senku worked with the swallows he had committed to repeat the experiments with.

They spent the past days adding shelves into the lab where he placed the swallows and some pots at times. A messy area it became.

The weeks spent by with them working to survive. Checking the land. Gathering plants. Showering. Sleeping. Experiments fails.

"Your going to be on your menstrual cycle soon" he said without importance as he moved the pots aside. "So take it easy and sit down when it comes" he said as he shook the small bottle of clay that contained nitric acid, looking at it intently as if he could uncover the whole structure by sight.

She turned to look at him. Realizing he had kept track of her period, something she didn't even do. Which embarrassingly caused her underwear to stain on modern days.

She picked the empty basket with few remains of plants they had, and she left to gather water and edible plants or meat if found.

"I'll. Be. Back" she said in terminator voice as she pulled close to her face her invisible cool glasses.

He gave a small chuckle with a soft smirk plastered in his face. "Hai"

He saw her come back after some time as she yelled waving in happiness. "I found grapes look!"

She immediately took it out of the basket and gave it to him as she took a small grape and ate it.

She made a funny face just like when someone ate a lemon or got constipation. "It's not grapes. Not grapes. Don't eat it" she stuck her tongue out making a 'blah' sound.

"Heh. Not bad" he said as he intently stared at her with a witty smile.

In an instant he change his witty smile to laughing his ass off as he saw her face. He then smirked when she recuperated, his plan returning to his mind. "They are grapes, bubble head"

She looked at him curiously. "What are you planning mad scientist?" She wiped her mouth as she tilted her head knowing that the boy ahead, the genius, had a plan.

"With the alcohol in liquor, I could combine the nitric acid and the ethanol to make nital."

He explained as little images appeared out of nowhere as his smart board. "It's literally an industrial-strength etching agent."

She was left confused but nodded with a puzzled face, like she always did at school when her teacher explained.

He noticed though, and chuckle at her cute expression, a small thought building up in the back of his mind.

"I'm glad then" she smiled happily as she stared at his smirk. She was glad she could have helped him, even if she merely found it on the way and thought it would make him happy to eat those beriries.

"I'm glad too" he turned around and that day they began to make wine.

She was sent to bring more grapes and Senku stayed to prepare the set up to squeeze them. She returned with the basket filled up.

Taiga saw him sitting down slowly squeezing one grape at a time "Wouldn't it be better to do it like they did it?" She asked as she observed the grumpy Senku.

He looked at her and attempted to decipher what she meant "I mean- you know. With the feet" she timidly suggested as she imitated the action of feet squashing wine makers did.

He nodded as his mood lighten up at her presence and told her to step in. She grabbed a small pot and washed her feet. She then stepped into the large pot gently squashing them at each step, picking up the pace as she regained confidence. He did the same and stepped into another pot.

He smirked as he saw her enjoy stepping on them.

She carefully held Senku's coat up to avoid staining it. She smiled like a little amused kid. Turning to look at him. "You have no idea how much I want to splash you with this wine!"

His smirked vanished and was immediately replaced by a funny surprised look. "That was the least of the things I thought you were thinking about"

He then smirked with a faint chuckle.

She finished first and she stepped into his pot by taking a big step and grabbing him to gain balance and not fall. The pot was slightly smaller.

"Oí!" He yelled as he held her from falling. Her body almost molding into his like their nights. She looked back and smiled "you slow captain"

"This is a small pot for the both of us"

"Two heads are better than one!"

"Yeah. But you are a millimeter from me we can barely move due to our bodies being stuck together by the diameter of the pot." he said as he felt her body move which rubbed his skin. She looked down to see where she had left to step on, ignoring his last remark. 

"It still works. It isn't that small, lettuce"

She stuck her tongue out at him in a playful way, looking up. Encountering his thin lips and  red eyes that stared at her. His usual emotionless calm look that always looked annoyed or cold. Usually, when he had that look it meant his attention wasn't caught. 

She caught her breath at the sight of the closeness they were in. She had kept his hand she yearned to hold for long terms, and she used it for balancing purposes. "It isn't that bad Ishigami-san" she nervously spoke out as she tightly held his hand as if they were going to dance.

"I guess you're right" he looked downward at where he stepped just like she did, but he met her head blocking most of the view. He dealt with it and just stepped where he saw.

Once they finished, she stepped off the pot, the dirt attaching to her wet feet, just like Senku's purple feet.

"Making wine couldn't be easier" he said as she poured the pot into a tall one. "Crush grapes and raisins and stuff, put it in a container" he began to mix it using a stick they had carved out of wood. "And just mix it every day until it's done."

Night followed by not before a warm fireplace moment filled with silence, small glances from her to him with small sincere, shy smiles within each other.

Their night was silent just like their routinely fireplace gather. The crickets didn't sing like usual. The moon shown bright, and the numerous stars filled it in company. Taiga on the other hand, had multiple sleep paralysis any time she wanted to fall asleep.

The room was in silence as she stared around in search of anyone, but she only found normal shadows that crept in their room and her own breath.

She had felt something grasp her, but it wasn't Senku. His body laid asleep his figure tucked into his bed soundingly.

The hand had been way too large with sharp nails that had wrapped around her neck choking her. It wasn't him. She trembled as she kept looking around, biting her lip firmly.

Before panic could crawl into her veins completely, she got up and climbed down their tree afraid to feel again.

She observed the deep forest whose shadows seemed to dance, but she concluded it was the wind that shook them away. She wondered if she would experience her nightmare if she entered the forest. If it was safe. What if it did happen?

Her troubled mind traveled through inquiries.

Taiga took a step into it. Defying her fear inside wondering if it was going to be the solution to her problem. She gulped her fear as she hoped for a fragment of peace at last for her troubled mind and heart.

Senku, on the other hand woke up and went in search of her after she didn't appear after 23 minutes and 13 seconds. He followed the sounds of growled grunts, and thuds that derived from deep inside the forest.

He found her kicking the tree continually, her legs bleeding, her knuckles red from pain. He didn't know what to do. He was speechless. Was there even something to say?

She punched the tree with anger, as she desperately cried out loud. Each time harder and harder which made Senku react.

"What are you doing moron?!" He was shaken up by her actions. "Stop. Stop" he sternly yelled as he grabbed the tigress's arms from behind as she fought his gripped and continued to punch.

To his surprise, she stopped without giving off a fight once she realized the scene. She leaned into the tree as she brusquely shook her arms away from him to then hide her face in her arms. She was breathing heavily with frustration. Anger. A beast restraint.

She gave off a last hard punch. Tree fragments falling down leaving the bare inside of the tree open.

Then her cries silenced....

Her body shook from containing her breath so that she didn't cry out loud.

He immediately turned her small tense figure around when he return to his senses and began to yell at her a whole lecture his hand on her cheek rubbing her tears away in a toughen manner but still gentle. "What are you doing in the middle of the night you moron. You're harming yourself. Look at your hands and legs! Are you stupid! Why are you-"

Her angry look had soften as she cried and looked down at the ground, embarrassed and troubled. Her hand on her face frustrated. She melted into calm and comforted by his delicate touch of his hand on her cheek.

He closed his eyes, annoyed. "What's wrong Taiga?" He blurted out with desperate confusion as he returned his preoccupied look to her teary ones.

"...I'm sorry.....I don't know what's wrong with me. I don't know what the problem is anymore." She began to cry again as she reached for his coat.

"I don't know what is wrong with me anymore. I don't know." She placed her forehead on his chest "I don't know." She repeated one last time in anguish, her voice fading into complete small cries.

He rubbed her back with one arm "let's go up" He murmured as he pulled apart knowing that being outside was dangerous and desiring to put her to sleep. "Don't do this again" he sternly pleaded as she nodded wiping her own tears. They went back into their beds, Senku sleeping beside her.

"Why were you doing that?" He asked with certain anger.

"...I couldn't sleep. So I went out into the forest...thinking that..." she said as she seemed confused herself "I thought that. Being in the forest at night would take my fear away, and then I stayed there to kick, to....kick. But I got out of hand."

He analyzed her words knowing she had more reasons. "Stop crying" he said as he wiped her tears 'annoyed'. "We don't know yet."

"It's not only that. But I don't...know what the problem is. I simply can't figure out no matter how much I think or try not to think. I just feel this way. And I wasn't hurting myself" she spoke in her hoarse voice as she pouted letting out a small faint laugh.

"Your body shows otherwise" he sternly pointed out.

Senku turned around giving her his back. He would never think he would end up next to a girl in bed. This girl, the tigress, was a complete enigma.

"Taiga"

She hum in response.

"Don't harm yourself that way. You'll break a bone and then you won't be able to move."

"That's why I have you doctor stones" she joked with a small smile. Senku gave a glare despite being turned away from her.

"I wasn't harming myself"

"Your body doesn't show that" he sternly said.

"I was actually kicking. Practicing. But I got out of hand, Senku." She looked away "I won't harm myself, so don't worry Senku"

She looked at her knuckles that weren't visible in the dim light of the moon, and felt the aching pain from her legs against the blanket "not again" she murmured in a breath.

Senku heard her comment but didn't question it. He closed his eyes instead and when he was about to fall deep into sleep, he jumped a little, barely noticeable, as he was pushed into the calm darkness feeling her hands in his back. Her forehead against him. His sleeping dart draining him in a subtle way.

At nights, she was more sensitive apparently. Nights filled with her cries and her sniffs. She contained herself up used to being reserved, and strong to manage her pains.

Taiga was incredibly miserable one night. She sat up gripping her thighs tightly in suppression. She was scared. She wondered if she should give in into him, if she should accept his help, if she should need him. If it was a good idea to trust him.

She got off her bed and gulped her pride and fear away.

She walked towards his bed carefully as if she was walking in mine lands. She looked ahead yet she observed everywhere. Looking at the shadows, listening to the sounds. Feeling that at any moment she would be dead. Consumed in fear. She was just scared, terrified.

"Senku" she bashfully shook him awake, tears rolling off her cheeks as she bit her lips to drink her vocal cries.

He woke up with Asian looking eyes, oblivious to the situation, until he observed her tears and saw her hug herself tightly as she stood trembling in a manner he had never seen her do. "C-can I... sleep beside you?" Her voice crack through her sentence.

He made space and she settled down into the hammock that sunk them together. He wiped her tears away as she felt more than pathetic, but cared for as she felt her head being rubbed as she hid deeper into his