11th Episode — Numerous Challenges

"Salt is necessary. Having it would be helpful."

Oomori murmured in agreement with Hayato's condition.

To obtain salt not producible within the agricultural high school grounds, one must either go to the sea or explore the city.

Both options involved zombies wandering about, carrying risk of infection through bites.

If someone brought it, that would be best.

Oomori's positive stance on safely acquiring supplies was natural.

"I have a question for you, but first, let's discuss the car. Mr. Kobayashi, you were knowledgeable about vehicles, correct? What do you think?"

Oomori directed the question toward the teacher standing near the wall, in his thirties.

Kobayashi briefly showed a tense expression, then regained composure and spoke.

"Is that car yours?"

Oomori crossed his arms, watching Hayato and Kobayashi’s exchange intently.

Hayato hesitated at Kobayashi’s question, then answered honestly.

“No. I selected the SUV from abandoned vehicles within the city. The area is overrun by zombies. Please understand this as an emergency evacuation.”

Emergency evacuation referred to a legal justification for illegality defined in Article 37 of the Criminal Code.

Acts performed out of necessity to avoid imminent danger to oneself or others—life, body, freedom, property—were not subject to criminal liability.

Thus Hayato’s act of taking the vehicle was justified as necessary to protect Yui’s life in a world overrun by zombies. The necessity outweighed the violation of the vehicle’s owner’s rights, thereby negating illegality.

Hayato had learned about emergency evacuation from comment threads on videos about the East Japan Earthquake.

After hearing the explanation, Kobayashi relaxed slightly and offered a faint smile.

"No, of course I understand that. I thought it would be faster if you were driving your own vehicle."

Kobayashi, who seemed more knowledgeable about the law than Hayato, replied with a wry grin.

"What I’d like to know is battery replacement."

"To replace the battery, there are several challenges. The main one is avoiding the wrong battery choice. Memory backup procedures also need attention."

"Wrong battery choice?"

Hayato asked, not grasping the point. Kobayashi, sensing Hayato’s lack of knowledge, explained carefully.

"Car batteries come in many types. Even for the same model, the battery type varies by year and trim level."

"I see."

For example, selecting a battery with different terminal positions may prevent the power cable from reaching, making installation impossible.

That’s right.

It’s possible to bring back a battery from a vehicle repair shop without checking, only to find it unusable.

Hayato, who had assumed any battery would do, felt a cold sweat form inside.

He might have mistakenly believed his own poor workmanship was to blame, and forced the connection until it broke.

Hayato realized, even from just the first explanation, that listening carefully to someone else was worthwhile.

Additionally, choosing a low-tier battery may shorten its lifespan or reduce starting performance in low temperatures. What if the battery fails while surrounded by zombies?

That would be the end.

The battery size must match the vehicle.

Even if the size matches, a low-tier battery is still unusable.

Hayato, who had thought any battery would do, recognized his mistake.

"When selecting a battery, refer to the model number marked on the top surface, but a matching model is not available everywhere. Even if I teach you how to replace it, you must find the part yourself."

"A sigh would be appropriate."

Just hearing the first issue made Hayato feel the difficulty level was too high for him.

Yet the issues pointed out by Kobayashi were not limited to batteries alone.

"Next is memory. For example, if the vehicle has an idle stop system, replacing the battery without performing backup procedures may cause performance issues during operation."

The vehicle Hayato was operating might therefore suffer performance issues.

He should perform a backup if he dislikes the risk, but Hayato did not know how.

The system in question, "idling stop," was not something Hayato understood.

"Fuel procurement is difficult. The government reserved it for emergency vehicles, then added fuel stabilizers to extend shelf life."

Fuel stabilizers were additives that suppressed oxidation, degradation, and tank corrosion.

Ordinarily, gasoline became unusable within six months due to oxidation and evaporation.

With stabilizers, gasoline remained viable for one to two years. Doubling or tripling the dosage further slowed degradation.

Raw materials included butyl hydroxytoluene, butyl hydroxyanisole, and ethylenediamine derivatives—all domestically sourced.

Manufactured by domestic chemical producers.

Thus, gasoline lasted three to five years under normal conditions, and up to six to seven years in ideal environments.

Substitutes also exist: phenolic compounds, amine compounds, sulfur compounds.

All domestically produced. Each lasts two to four years, three to five years, two to three years respectively.

"Currently, with stabilizers added, the fuel has been stable for about two years. It can still be recovered and used, but after one year from now, it will no longer be usable."

"So the gasoline will remain usable for another year?"

"Even if you go to a station with remaining fuel, you cannot recover it unless you insert the hose into the underground tank, connected to the pump."

Even when vehicles become operational, fuel will degrade after one year.

Kobayashi pointed out this issue as well.

The teachers listening also exuded an atmosphere suggesting they wanted to stop Hayato.

But Hayato had no problem, since once stored in spatial containment, the state of storage is preserved.

— Spatial containment can't be shown, though.

Hayato pondered internally.

Transporting the vehicle onto the agricultural high school’s grounds, collecting batteries and gasoline, handing them to Kobayashi, and having Kobayashi perform the work would proceed smoothly.

But the power of spatial containment cannot be disclosed.

That meant Hayato would have to carry out all tasks alone.

"Still, the vehicle is necessary. Teach me. Gasoline needs only last one year. I will transport the required quantity of supplies."

Kobayashi gave a slightly troubled expression in response to Hayato’s words.

"That is acceptable, provided you ensure your own safety."

Kobayashi might have stopped Hayato if he had been one of his own students, deeming it too dangerous.

But Hayato was a graduate of another school, and even under the old standard of twenty years as adulthood, he was already an adult.

"Frankly, why do you need the vehicle?"

"Supplies in the city are dwindling. I thought it better to evacuate to a safer location than risk starvation."

"That is a reasonable justification."

After hearing Hayato's explanation, Kobayashi found it increasingly difficult to say no on grounds of danger.

Without access to supplies, starvation would follow.

Moving before that point is a rational survival strategy. It is a necessary action.

If there are objections, the only option is to accept them at Kirioka Agricultural High School. But Hayato is not a teacher or student. He is an outsider.

When food runs out, outsiders are not accepted.

"I can teach you how to operate a vehicle. I will demonstrate later using my own car. That is all from me."

After Kobayashi relayed the conclusion to Omori, Omori nodded.

"We accept the terms. But please, Kumakura, be cautious for your own safety."

"Of course. It is my life."

Hayato was afraid of zombies, but that was a horror-based fear, not a threat to life.

Oomori swallowed the second warning, watching Hayato's calm demeanor.