Chapter 25:

Isekai biology course with Sora-sensei

The Heracle's Diary - My Story in Another World


   In my world, Cerberus is known from mythology as a huge three-headed dog with lion’s paws and a snake-like tail, guarding the gates of hell. It’s a creature that’s been feared and admired in stories for centuries.

   But here? The reality is a little different.

   In this world, Cerberus isn’t a single legendary monster but a race. They belong to a group called Mystics, one of the four main intelligent races: Demons, Beastmen, Elves, and Mystics.

   Here’s a quick breakdown:

   Elves are easy to spot with their long ears, flawless skin, and natural beauty. Their subraces include High Elves, Forest Elves, and Dark Elves. 

   Beastmen are humanoid creatures with animal traits like ears, tails, or fur. They’re not great at magic, but they’re incredibly strong. Wolfmen, Catmen, and Lizardmen are common types of Beastmen. 

   Mystics are special because they can change between a human-like form and their original form. We have for example: Dragons, Phantoms, or Cerberuses. 

   Demons are a catch-all category for everything else, like devils, vampires, and dwarves. But in the case of demons, most of them look exactly like normal humans, with just small details. Vampires, for instance, have pale skin, and dwarves are shorter in height.

   But, let’s go back to Cerberuses.

   In their true form, Cerberuses do look like the ones from my world’s mythology—giant three-headed dogs. But they don’t start that way. When a Cerberus is born, it only has one head and looks like a small puppy. As it grows older, it gets bigger, and new heads start to form.

   Here’s the interesting part: each head has its own personality, like siblings sharing the same body. However, the “first head” is the leader, and the others depend on it.

   When a Cerberus takes its human form, things get even more interesting, since each head turns into its own human body. So instead of one three-headed creature, you get three separate people who are all connected by a shared consciousness.

   And why am I talking about Cerberuses? Because I’m currently playing chess with one.

   Across from me sat Bel, the little boy with floppy dog ears and a determined look on his face. The chessboard between us was set up neatly, pieces scattered as the game reached its final stages. He leaned over the board, studying it carefully before finally moving his knight.

   “Not bad,” I said with a nod. “You’re clearly getting better at this.”

   Bel looked up at me with a proud smile, his tail wagging slightly. “Really, big brother?”

   “Of course,” I replied as I moved my queen into position. Then, with a small smirk, I added, “Checkmate.”

   Bel stared at the board, his eyes widening as he realized he’d lost again. His ears drooped, and he let out a small huff of frustration. “Aww! How do you always win, big brother?”

   “It’s just experience,” I said, leaning back in my chair. “You’ll get there eventually. You’re already improving a lot.”

   Bel’s expression softened at the compliment, though his tail wagged begrudgingly. 

   “You’re amazing, big brother.”

   “As expected of Master,” Luna said, while she had been standing quietly to the side and watching the match.

   Two months had passed since the barbecue party.

   The Beastmen had been temporarily relocated to public housing while their village was being reconstructed. For now, the only ones left living with us were Luna and Bel. Victoria visited occasionally to discuss matters related to the village’s construction with Zephyra. She often brought Luke along. He claimed that it was for him to gain experience as the future village leader. But it was pretty clear that Luke’s real reason for coming was to keep an eye on me and ensure I was taking good care of Luna.

   I couldn’t blame him for being overprotective. If I were in his shoes, I’d probably do the same.

   What caught my attention, though, was that every time Luke showed up, Chloe wasn’t far behind. She explained that she wanted to make herself useful to the future village, so Victoria had started teaching her economics and management. It seemed like a good excuse—until I noticed her glaring daggers at Luke whenever he so much as looked in Luna’s direction.

   And then, I had a strange realization of the current situation.

   Luna is often checking on me as part of her maid duties. 

   Luke is often checking on Luna, when she is checking on me. 

   And Chloe is checking on Luke, who is checking on Luna, who is checking on me…

   …But, let’s go back to Bel.

   As I mentioned, Bel is a Cerberus, and a very young one at that—about 7 or 8 years old. Zephyra had pointed out something odd: his presence in this area. Cerberuses typically live in mountainous regions, far from civilization. They’re known for being fiercely attached to their roots, rejecting new technologies, and keeping to themselves. In short, they’re withdrawn by nature.

   But then I’d look at Bel and wonder how could that possibly be true.

   He was curious about everything.

   Whenever Zephyra was in her workshop, Bel could almost always be found sneaking in to watch her work. He’d ask a hundred questions about what she was doing and how the machines worked, much to her initial annoyance. Then there was his endless energy—he’d often tug at my sleeve, asking me to read him a book or play a game with him.

   Watching him dart around, ears wagging and eyes sparkling with excitement, I couldn’t reconcile the image of this lively, curious boy with the withdrawn nature his kind was supposedly known for.

   Recently, Bel had developed a fascination with a TV program that showcased interesting facts about the world. Every day, without fail, he’d settle himself in front of the screen, his eyes wide with curiosity as he absorbed every piece of trivia like a sponge. It wasn’t just idle watching, either—he’d repeat facts word-for-word later, as if he’d memorized them perfectly on the first try.

   That boy’s capacity for learning was astounding. He’d learned to read fluently and write legibly far faster than I ever did. Not only that, but his was cleaner, sharper, and frankly it is embarrassing for me to compare mine to his.

   Not that it bothered me...

   Not at all...

   Zephyra suspects that Bel has hyperthymesia, an exceptional ability to recall information and experiences in vivid detail. The possibility doesn’t surprise me. After all, I have it too.

   But as impressive as his abilities are, they also worry me. Bel doesn’t remember anything about his life before I found him, injured and alone in the forest. It’s likely that he experienced some terrible trauma and that the memories are locked away, hidden deep in his mind. Instead, for reasons I still don’t understand, he latched onto me and convinced himself that I was his older brother.

   At first, I didn’t know what to make of it. Should I correct him? Should I push him to remember? But Zephyra advised against it. 

   "It’s better not to make him aware for now." - That's what she said.

   I reluctantly agreed. 

   Regardless, those two months passed peacefully. We settled into a quiet routine and it felt like life was stable.

   That is, until one day...

Xa
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Corty
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SHURA
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 Yuu Hoshino
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