When we arrived at the hospital, I was ushered straight to the back without any wait.
"Hmm. The condition looks good—this should be fine."
Toki-san gave me a brief check-up—just a quick look, a few questions, and a nod of understanding to herself.
"Please sign this."
She slid a piece of paper my way.
Consent Form for Scheduled Vaccinations
Hepatitis B, Hepatitis C, Rotavirus, Hib, Pneumococcal, Diphtheria, Tetanus, Pertussis, Polio, Tuberculosis, Influenza, COVID-19, Measles, Rubella, Mumps, Chickenpox, Japanese Encephalitis, HPV, Meningococcal disease, Rabies... and more.
Even at a glance, it was quite the list.
"You probably received most of these in your original world, but since we have no medical records whatsoever, we're treating this like a clean slate. So rather than going from 1 to 10, we're giving you everything from 1 to 100. Here's the consent form. Preventing pandemics takes cooperation, and we really can't have you dying early from some illness, so—please."
When Toki-san gets serious, especially with her good looks, the pressure she gives off is no joke.
As I skimmed through the form, I was stunned by the sheer number of shots listed.
"All of these… in one day?"
"There are a lot, so we'll spread them out over a few days. Side effects can be a thing, too."
How long is this going to take? A month?
"There are combo shots too—like the 3-in-1s or 4-in-1s—so the total number of injections won't be that bad, right?"
"Exactly. It won't be as many as it looks."
"Now, these next ones are newer vaccines. They probably didn't exist back in your time, right?"
She pulled out another sheet. This one listed gonorrhea, chlamydia, syphilis, AIDS, and others—definitely things that weren't preventable by vaccine in the old days.
Honestly, I was glad to see them.
"You actually managed to develop these?"
I couldn't help but admire it.
"These were incurable diseases back then..."
I muttered. How did they do it? Genetic engineering? mRNA tech? Maybe horse or ostrich-based? Human-derived? Seems unlikely they'd still use animals...
"Even if there's no cure, you can still make vaccines. And even with treatments, some diseases leave lasting damage or take years to heal. Prevention is cheaper and better for public health."
"Fair enough."
"Also, men's healthcare is pretty much fully government-funded here. Still, it's better to get the vaccines and stay healthy longer. You get the idea?"
She pushed the form toward me again, insistently.
"Yeah, alright. Go ahead."
I signed the form without complaint.
As expected, I had fevers and other side effects. It took quite a while to finish all the vaccinations.
Author's note :
I'm firmly in the "get vaccinated as long as subsidies exist" camp.
Medicine isn't going to become some nanomachine miracle in the next hundred years, so I'm a big believer in grounded, science-based prevention.
As for the in-universe lore: people infected with Wolbachia have slightly higher core body temperatures. If you want a cruder take—it's noticeably warm "down there."
Because they're always running a bit hot, they burn through calories faster, stay lean, and have highly active immune systems and metabolisms. They're less likely to show symptoms for mild illnesses and may become asymptomatic carriers. This means that without pre-sex health screenings, infections could slip through. In a world without acquired immunity, someone like Hisui is at risk.
Note: the metabolism boost from Wolbachia is a quirk specific to this fictional world.
Over a hundred years, cold-type viruses like the flu mutate so much they might as well be completely different. Think of how Spanish Flu was technically just an influenza strain—makes you realize vaccines really are essential.
Go back 200 years, when nutrition was worse, and Wolbachia hosts—who had lower starvation tolerance—tended to die off from malnutrition rather than disease. As a result, gender ratios were more balanced back then.
While Wolbachia infection may have its upsides in resisting illness, malnutrition was the real killer. But with nitrogen-fixing breakthroughs like Haber-Bosch, global nutrition improved, infant mortality dropped, and now Wolbachia carriers are surviving and spreading again.
In famine regions like parts of Africa, things are getting wild—states are nationalizing sperm and male citizens as strategic resources. Yeah, it's intense.
As for concerns about livestock industries collapsing—Wolbachia is passed maternally, not like bird flu or foot-and-mouth disease, which spread explosively and kill fast. So while outbreaks could be an issue, uninfected individuals can still be sorted out. Tetracycline and similar antibiotics can "clean" egg cells to allow for male births, but that raises egg cell death rates and is incredibly inefficient—not to mention ethically sketchy for humans. So yeah, it's been classified as a forbidden technology for human use.
In animal farming, an outbreak could cause problems, but as mentioned earlier, we have ways to manage it. It's not game over.
Long-term human survival may depend on us developing natural Wolbachia resistance: suppressing chromosome changes, repairing them afterward, or the immune system learning to purge the bacteria. Lots of possible avenues.
The scariest thing? Some people—benefiting from boosted body heat or other perks—might secretly prefer to let Wolbachia stick around, even knowing it causes male population declines. A silent faction that wants peaceful coexistence with Wolbachia.
In the end, Hisui, who is uninfected and healthy, is something of a rarity.
That also explains why males in this world tend to be so weak—the uninfected "errors" are born with weaker immune systems compared to infected individuals and often struggle with development.
And once again, this story is fiction. The human-Wolbachia stuff is all the author's imagination, so please don't take it too seriously.
One more strange note: HPV, the human papillomavirus, is often blamed solely for cervical cancer, but in truth, it causes a whole range of mucosal cancers.
The vaccine helps prevent not just cervical cancer, but also throat, esophagus, oral, anal, and rectal cancers—so it's not just for women. In fact, limiting it to women makes no sense.
It spreads through mucous membrane contact. You don't even need sex—just kissing is enough. It's said that over 50% of people are infected, and if you've kissed three or more people, the rate jumps to 90%. The virus incubates for 10–20 years before symptoms show, making it incredibly frustrating.
Thanks to media fearmongering, it's no longer mandatory in Japan, leading to an abnormally high cervical cancer rate compared to other countries.
Currently, subsidies are only available for women in Japan. Men pay full price—clear gender discrimination.
Globally, the recommendation is for both men and women to get vaccinated. In Japan, men have to pay 50,000 yen for the cheaper quadrivalent vaccine (3 doses), or 100,000 yen for the 9-valent version—out of pocket. No insurance coverage. That's outrageous.
Worst part? Calling it the "cervical cancer vaccine" is misleading.
So yeah, being told to get unsubsidized shots like the flu or now-unsubsidized COVID vaccines really grinds my gears.
I tend to obsess over drafts unless I just publish them, so since I wrote all this—out it goes. Sorry if it was a mess to read.