The Wildcat Smile
The battle robot pilot trainee who became a wildcat-like beautiful girl—Moon Naru.
Moon Naru, a sixteen-year-old male high school student who dreamed of becoming a professional battle robot pilot. His robot was The Pandemic Slayer, V-Killer. He named it during the COVID-19 pandemic. It was shortened from “Virus Killer” with the hope of eradicating the coronavirus.
His highs and lows were extremely polarized. His peak was as high as the summit of K2, the world’s second-highest mountain. His bottom was as low as the floor of the East Sea, that small ocean.
In early 2023, Moon Naru was still stuck at the local battle robot academy. He had finally succeeded in advancing to the 110 kg amateur class.
(I never thought I’d end up building up to the 110 kg class at a neighborhood academy…)
When you first start battle robots, you begin in the lower weight classes. After that, you usually climb the ranks in this order: 454 g → 13.6 kg → 27 kg → 54 kg → 110 kg. There are various other classes too, of course. For a professional debut, this sequence is the standard path.
(I thought someone at my level would get scouted by a pro team around the 27 kg class…)
Players who debut professionally usually transfer to a team-affiliated academy before reaching the 110 kg class. The earliest move at 27 kg, and the majority start at 54 kg. Staying at a local academy all the way up to 110 kg? That meant the chances of turning pro had become extremely slim.
After spending 2023 in a blur, it was suddenly mid-August. The second half of the 2023 season had reached its halfway point.
“If I win tomorrow too, that’ll be three wins and one loss. I’ll make it into the tournament!”
Moon Naru’s battle robot, V-Killer, had a record of two wins and one loss up to that day. Every single match had been incredibly short. All three full matches could fit into one short-form video.
The maximum time limit for a single battle robot match is 3:00. The median duration, based on the 2022 season of South Korea’s pro league RCLK, was 1:37. Anything under 1:10 was a refreshing, overwhelming victory for the winner and a humiliating crushing defeat for the loser. Anything over 2:00 felt equally brutal for both sides—an absolute bloodbath. In other words, when he won, he was endlessly destructive. When he lost, it was total annihilation.
“I’ll get my flu shot on the way home. See you tomorrow!”
That year, the flu had started spreading ridiculously early. Who could have predicted a flu outbreak in the middle of summer? As a result, vaccinations had begun in early August.
“You’ve got a match tomorrow. Is that okay?”
“It’s not like getting the flu shot means I have to rest for a whole week, right?”
The flu vaccine had been developed and used for a long time, so its side effects were relatively mild. At least it wasn’t as harsh as the COVID-19 vaccine. That one had required a full seven days of complete rest after the shot. Even if your body felt a little off, it wasn’t a big problem for controlling a battle robot.
On the way home after the match, he stopped by the clinic near his house.
(Today’s bandage is pretty cute…)
After getting the shot, he returned home. V-Killer was half-disassembled and stored under the bed. That was only possible because of its relatively small size for a 110 kg robot. Most were around 2.5 m wide by 2.5 m long by 1.5 m tall.
Moon Naru washed only his hands before flopping straight onto his bed.
“At least I don’t have to shower after the shot… ow ow ow, my arm…”
No matter how mild the side effects were, his body still ached. A vaccine had to use some form of pathogen, after all. It was impossible to completely eliminate the pain.
“Ugh… today was way too intense…!”
In daily life, Naru had an easygoing, gentle personality. But the moment he grabbed a battle robot controller, he turned fiercely aggressive. Because he had fought at a machine-gun pace, he was utterly exhausted. He had knocked out his opponent in just 0:42. Even V-Killer’s carbon-fiber body was covered in countless small scratches. The steel armor wrapped around it like a belt had its paint chipped in dozens of places.
Dragging his vaccine-weary body, he collapsed onto the floor of his room and fell asleep.
(I can still make my pro debut… right?)
Moon Naru was beginning to doubt whether he could ever turn pro.
The next day at 6:30, he woke up. The first thing he saw was the unpainted silver blade of V-Killer. The moment he caught sight of his own reflection in it, he let out a piercing scream.
“Kyaaaaaaaaaah!! What the hell happened to my face!!”
(What the—?! Even my scream sounds like a girl’s now?!)
Until yesterday he had definitely been a guy. When he woke up, he had become a beautiful girl. Her features were sharper than a typical cat-like face but cuter than a snake-like one. If he had to describe it, she looked like a wildcat-type beautiful girl.
The fact that even her scream came out sounding like a vulgar “pterodactyl cry” left Naru completely flustered. (There was, of course, no actual evidence that pterodactyls made sounds like that.)
His mother, who had already set the breakfast table, called out for him.
“Why is some girl screaming first thing in the morning? Naru, come eat…”
“Are you Naru’s girlfriend? Where did our Naru go?”
“Mom! I am Naru!”
Naru explained the whole situation to his mother. Along with the explanation, he showed her a paper published in a world-renowned academic journal.
"Report on Adverse Effects from 75 Types of Influenza Vaccines, 2022"
⟨ Side Effect Summary ⟩
The paper literally listed side effects caused by seventy-five different flu vaccines. The part explaining the current situation could be summarized in three lines:
1. There is an extremely rare side effect that can occur when certain flu vaccines are combined with certain medications.
2. With a 1 in 19 billion chance, a male can be completely transformed into a female.
3. Unfortunately(?), there is currently no way to reverse it with modern medical technology.
“Of all the people in the world, that one-in-nineteen-billion chance had to land on you… It’s Liberation Day, so school is closed, but you still have to go to your match, right?”
“Of course! Just because I’m a girl now doesn’t mean I can’t pilot a battle robot.”
Since it was Liberation Day, he didn’t have to go to school. All he needed to do was compete in the amateur league match and come straight back. It was a sporting event, after all—there were no holidays.
A sports league that enjoyed the highest global prestige yet took breaks on every holiday? That would be the weird one. You were supposed to boost viewership on holidays, not rest.
Naru decided to wear the same clothes he had worn as a boy. He only packed V-Killer, the controller, spare parts, and various maintenance tools. He rode with his father to the arena.
The first person he ran into after arriving at the venue was his close female friend, Lee Cheong-bi. They had first met at the battle robot academy in early 2023. Up until now they had simply been friends who felt like siblings. Well… maybe sisterly friends now?
“Who are you? Why are you wearing Naru’s clothes?”
“Cheong-bi, it’s me! I’m Naru!”
Naru showed her the paper. He used the AI summary feature provided on the journal’s homepage. He had it summarize only the gender-transition side effect section.
“One in nineteen billion, and it happened to you?”
“If you can’t get into a pro team, how about becoming an idol instead?”
“With a face like that, you’d be more than enough, right?”
“Only now you’re telling me to become an idol? How?”
“I’m kidding~! Someone like you becoming a pro battle robot pilot would be a piece of cake!”
In truth, Cheong-bi knew almost nothing about idols. She had once received a casting offer via SNS DM. The account name? ‘@ahs_official’. She thought it was a recruitment offer from a rising powerhouse in China’s CRCL league. She assumed it came from AHSCIS Robotics/AHS. Overjoyed, she screenshotted it without even reading the full message and bragged to her friends. When their reactions seemed strange, she looked at the account name again. It turned out to be an audition invitation from a major Korean entertainment agency—AHS Entertainment.
She had been so happy that she completely forgot about it until now. The battle robot team AHS had a completely different SNS handle: ‘@ahscis_robotics_2019’. Both accounts used the same “AHS” profile picture. The battle robot team’s nickname was “The Ultimate Idols,” precisely because the initials matched those of AHS Entertainment.
(Ugh… I feel like all my strength just drained away…)
Moon Naru still wasn’t used to her new female body. Moving the robot felt harder than before. In reality, even a healthy adult man would struggle to move it easily. After all, it weighed 110 kg—more than most grown men.
(It moves on its own power, so using a cart feels weird somehow…)
Battle robots were very different from the humanoid machines people usually imagined. They weren’t the bipedal robot fights that usually came to mind. They were basically reinforced RC cars with weapons attached.
Ninety-eight percent of pilots used RC-style controllers—either RC car or RC plane controllers.
Seventy-five to eighty-five percent of battle robots looked roughly like this: weapon-equipped vehicles. Those “weapons” were mostly spinning blades or electric flippers. Less commonly you would see electric axes or hydraulic jaws.
Eighty to ninety-five percent moved in a way similar to robot vacuums. Probably because both were wheeled robots. In a sense, they moved like wheelchairs—whether manual or powered didn’t matter.
To explain it more specifically:
1. There are 2n drive wheels.
2. The left and right wheels must be able to move independently.
3. To go straight, both wheels rotate in the same direction.
4. To turn, they rotate in opposite directions to change heading.
The two most important advantages of this system were:
1. Simple structure.
2. Ability to change direction on the spot.
The August 15 Liberation Day match that would decide whether they advanced to the tournament. Who would Moon Naru and V-Killer be facing?
“Who’s my opponent today… kyaaaaaaaaaah!! Why is the bracket like this?!”
(There’s that pterodactyl scream again. I really don’t want to make that sound…)
Once again letting out a pterodactyl-like shriek, Moon Naru stared at the matchup. Just who was the opponent that made her react like that?