Isekai biology course with Sora-sensei

   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 legendary beast but a race. They belong to a group called Mystics, one of the four main races:

   Elves who have long ears, flawless skin, and natural beauty. Their sub-races include High Elves, Forest Elves, and Dark Elves. 

   Beastmen - 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. 

   Everything else is categorized as Demons, like devils, vampires, or dwarves. Most of them look exactly like 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 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 alpha, 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, 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.”

   “Really, big brother?” His tail wagging slightly.

   “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. “You’ll get there eventually. You’re already improving a lot.”

   “Really?”

   "Of course."

   “Master is right,” Luna said, while she had been standing quietly to the side and watching the match. "Just keep trying."

   "...One more game, please."

   "Sure." I said with a smile.

   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 re-construction. 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 he wantted 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 started teaching her economics and management. But when I noticed her glaring daggers at Luke whenever he so much as looked in Luna’s direction, I knew the real reason.

   Then, I had a strange realization.

   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…

   …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 and rejecting new technologies. In short, they’re withdrawn by nature.

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

   He was curious about everything.

   Whenever Zephyra was in her workshop, Bel would sneaking in to watch her work. He’d ask a hundred questions about what she was doing and how the machines work. 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, he’d settle himself in front of the screen, his eyes wide with curiosity as he absorbed every piece of trivia like a sponge. And it wasn’t just idle watching. 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 and write far faster than I. Not only that, but his writing was cleaner, sharper, and frankly it is embarrassing for me to compare it to mine.

   Not that it bothered me...

   Not at all...

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

   But that also worries 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, that locked his memories away. Also for some reason, he 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...