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The seaside village of Shibuya is a curious place to live. During warmer weather, it's considered a popular tourist attraction with people visiting to hear about the different stories regarding the rumored merfolk that inhabited the surrounding sea. But sadly, once the weather turned chilly, the off-season kicks in. During that time, most businesses closed and the environment becomes less lively.
Granted Shiki was used to how Shibuya changes during the years, but this year was different. For you see, she was hiding a secret from the other locals. Just this summer, she befriended a merman named Neku who was injured from a dangerous tsunami. While he initially had a bitter personality, he soon warmed up to her, granting her first kiss in a moonlit night. She was able to heal him within a week, but to her surprise, he had made a deal with a sea warlock who supposedly gave him special items that not only allowed him to walk on land, but also granted Shiki the ability to turn into a mermaid. Since then, the two have had adventures on both land and sea.
Why is this so important? Well this was the first year Shiki was spending the approaching winter with an actual merman. While she waited for him to return to the surface, she did research on what fish do during colder weather in hopes of helping Neku warm up...if that was even needed. After all, different fish have different adaption methods, so they same was most likely true for merfolk. And according to her research, fish either migrate to warmer waters, undergo a special type of hibernation known as torpor, or adapt to the cold. All that was left was to see if merfolk fell under one of those three categories.
Of course, the answer soon came to her when the merman in question showed up on her doorstep with pale blue skin, shivering like crazy and only wearing his purple pants. His hair was damp, indicating he had recently emerged from the ocean, although that didn't help keep him warm.
"Neku?!" Shiki panicked. "What happened?!"
"I'm fine," Neku insisted as he entered the Misaki residence. "This always happens during the cold. I normally move to warmer waters around this time."
"Then why didn't you do that?!" Shiki asked.
"'Cause I never made any human friends until now," Neku revealed. "I wanted to spend the winter with you this year."
While Shiki was touched by this reveal, she was preoccupied with gathering blankets for her friend. The fireplace was already lit, so she quickly escorted Neku towards it and gently sat him down. Yet even as the flames dried him off, his skin remained unusually blue. Of course, that got Shiki concerned, since she was still unfamiliar with actual merfolk biology.
"Is everything okay?" the brunette asked, slowly sitting next to the merman. "You still look cold."
"I told you, this always happens," Neku repeated. He held up his arm. "Our skin turns blue when the weather gets colder. It reminds us to move to warmer waters before our tails freeze solid."
Shiki gingerly touched the merman's arm. It felt so cold. "So it won't change back no matter how much you warm up?" she checked.
Neku slowly nodded. "We're only half fish," he continued. "But if there's a slight change in temperature, it will kill us."
"You're cold-blooded," Shiki concluded. Her hand shifted from his arm to his cheek. This realization broke her heart. Even after being able to turn human when needed, Neku was still a merman. His temperature changed depending on the environment, so he can't warm up naturally.
And yet, Shiki noticed Neku was reacting to her hand. He let out a sigh as his eyes slowly closed. "This feels nice..." he muttered. "You're so warm."
"You like this?" Shiki asked as her thumb gently stroked the merman's cheek.
Neku sighed again as he leaned in, pulling the brunette closer to him. This surprised her, but not in a bad way. This wasn't the first time they cuddled together, but not like this. His movements becoming more sluggish as he drifted into a deep sleep meant he was undergoing torpor. It was most likely due to how he was still in a cold environment, even with the added heat from the fireplace.
Shiki knew torpor was more common for birds and mammals, but she had heard that it sometimes happens to certain types of fish. She also knew it was different from proper hibernation, being unplanned and only occurring for a few hours. So after successfully prying his clingy body away from her, she nudged his body closer to the fireplace and got back on her feet.
It was time to put her plan into action.
When Shiki learned about torpor a few months ago, she bought a small, plastic swimming pool and a bag of dirt. So while Neku was resting by the fireplace, she got out both items and set them in the living room. She wasn't quite sure if Neku was the type of merman who buried himself in mud, but it didn't hurt to check. So she mixed in salt water and dirt to create a makeshift bed. It did take a while for the mud to settle in, though.
Just as Shiki finished stirring in mud, a familiar glow caught her eye. Sure enough, Neku's pants vanished as his legs were replaced by a familiar purple tail. The brunette gasped, knowing that just as freezing temperatures can cause issues for fish, the same was also true for heat. She carefully lifted the merman and set him down in the small pool, hoping he would feel comfortable about the adjusted setting. Sure enough, he let out a small sigh as his body instinctively shuffled around. That movement allowed his tail to get buried in the homemade mud. Once he was comfortable, he smiled in his sleep as he rested in the pool.
Shiki was so happy to see how content the half-fish boy was in her handiwork. His skin was still pale blue, but he did stop shivering. In a moment of curiosity, the brunette girl gently touched Neku's forehead to check his temperature. Sure enough, he was feeling less like an ice cube. But it was this seemingly innocent gesture that made her notice new things.
His bright orange hair was cut short some time ago as part of his deal with that sea warlock, but he didn't cut it again since, resulting in its original long length gradually returning. His eyes were closed, but Shiki did notice he had rather long eyelashes. There was also how smooth his skin felt, his slender build... Even how the burning flames made the purple scales on his tail shine. His beauty was so inhuman, yet so...perfect.
"Oh Neku..." Shiki sighed, admiring the sleeping merman. "I don't know if you can hear me in this state, but I'm so glad I met you. Learning about your kind amazes me. I love hearing about what it's like living under the sea. Thank you so much for letting me be part of your world."
At that moment, Shiki noticed snow was starting to fall outside. In a matter of minutes, the streets will be covered in white. Of course, she was mostly looking forward to seeing Neku's reaction to snow. He must have spent so much time only knowing of tropical climates, so a winter wonderland would be unfamiliar to him. Granted he was still undergoing torpor, so at that moment, the amateur marine explorer whispered a promise into his ear.
"I can't wait to show you my world as well."
A few hours had passed since Neku had undergo torpor. He let out a small groan as he returned to the waking world. It took a while for him to realize he was now laying in a kiddie pool with his tail buried in mud. Although he was momentarily confused, he did admit it felt rather comfortable, so he snuggled deeper into the mud.
"Sleep well?"
That voice came from Shiki, who was walking over to him with two mugs. She was now wearing a dark grey sleep hoodie with matching sweatpants. She smiled as she knelt next to him and held out a mug towards the merman.
"Sorry I fell asleep on you," Neku apologized as he accepted the mug. He peered into the ceramic object and saw some kind of dark liquid with white objects floating on the surface. He slowly took a sip, his curiosity turning into amazement.
"It's okay," Shiki reassured. "Now I know your kind goes through a special kind of hibernation in the winter."
"It doesn't happen often," Neku explained. "We move to warmer waters to avoid falling asleep." He picked up a white object floating in his mug. It felt unusually squishy.
Shiki let out a small laugh. "That's a marshmallow," she explained. "It's a type of sugary food you can eat."
"Marsh...mallow?" Neku repeated. He looked at the squishy object once more. After a few seconds of hesitation, he put it in his mouth and slowly chewed, trying to get a feel for how it tastes. Once he was pleased with how it tasted, he swallowed it. "Why have something like this floating in black water?"
"It's called hot chocolate," Shiki clarified. "And to answer your question, humans put marshmallows in it so it tastes better."
"That so, huh?" Neku muttered. He took another sip from his mug, this time swallowing a few marshmallows at the same time. "Hmm. Not bad. Is this what you drink during cold weather?"
Shiki nodded in response. "It helps us stay warm," she explained.
"So you drink to adjust your body temperature?" Neku checked. "Your kind has unusual customs." He took another sip of hot chocolate.
"Is that helping?" Shiki asked.
"Nope," Neku sighed. "But it's still tasty. I kinda like it." He snuggled deep into the makeshift mud. "Can you show me what other human customs you do in the winter?"
Shiki checked the clock hanging from the mantel. "It's getting a bit late," she noticed. "But don't worry. Tomorrow, I'll show you what Shibuya looks like covered in snow."
"Snow?" Neku repeated.
"Yeah, snow," Shiki replied. "It's a pretty sight. Even better than what the ocean looks like in the summer."
Neku smiled warmly at his human companion. "Cool," he agreed. "It's a date."