Awakening from his long sleep, the undying one immediately kicked his way out of the cabinet and jumped down.

He landed forcefully, then staggered for a moment. His hastily reattached arms and legs were still loose, not yet fully joined to his body.

But he was an undying one with regenerative abilities, and he happened to be brimming with vital energy.

"Hup!"

As he tensed his muscles, his slightly twisted limbs snapped back into place. The scrapes covering his body healed in an instant, and his desiccated flesh filled out as though thoroughly soaked in water.

Fully revived, the undying one looked down at his hands and feet and exclaimed.

"Oh! I'm brimming with vital energy! How did this happen?"

As he looked around, the officer standing directly before him stiffened her neck and spoke.

"Rash of the Tantalus training unit. Correct?"

The undying one promptly answered.

"Indeed! To be greeted by such a beautiful woman the moment I open my eyes! My life has not been in vain! This, too, must be Mother Earth's providence!"

"... Beautiful?"

"Of course! What else should I call a beautiful person but beautiful?"

His words were smooth, but so unexpected that the officer could not quite process them. She merely frowned.

"There is no time for wordplay. I am Lieutenant Colonel Callis Kritz, appointed Instructor of Tantalus, and also this facility's administrator. Furthermore..."

The officer opened the bundle and took out its contents. Rash watched curiously, then brightened as he recognized the object.

"Isn't that a World Tree leaf!"

"You recognize it."

Just as beasts had kings, grasses and trees had World Trees.

Unlike those of beasts, however, the kings of plants did not take human form.

Humans were the dominant species on earth, but only within the animal kingdom. Even the most arrogant human would hardly dare claim that humanity ruled over plants as well.

And indeed, plants retained their original forms, utterly unconcerned with what became of beasts.

Even the countless flowers and grasses that bloomed and withered had kings, but finding them was nearly impossible. The kings of plants took the forms of their respective species, making them difficult to distinguish. Even if extraordinary luck led someone to discover one, its life would end the moment it was uprooted.

Some trees, however, could live for thousands of years, and the same held true for their kings.

Tree kings lived anywhere from decades to millennia. Some had existed for so long that their whereabouts had become known.

People called them World Trees.

Having absorbed the earth's vital energy for thousands of years, they were said to have individual roots the size of small hills and leaves as large as great fans. Some people revered and worshipped these vast, sacred tree kings, born and raised alongside Mother Earth, as gods.

Rash the undying one was one such person.

"Of course I recognize it! Our tribe is closer to Mother Earth than anyone else in the world. How could I fail to recognize something so full of vital energy! Though the sacred ginkgo tree is nowhere near our home, we always yearn for it!"

To everyone else, however, they were merely rather curious, oversized trees.

Slightly valuable trees whose fallen leaves could be sold for money.

The officer spoke.

"Then you understand how valuable this is?"

"Of course I know its monetary value, too! I once tried to buy one, but it was damned expensive! The pittance I earned from hard labor wasn't nearly enough! In any case, thank you. My regeneration had been slowing for lack of vital energy! Thanks to you, I'm completely healed!"

The undying one nodded readily. The officer offering him the World Tree leaf, however, was inwardly bewildered, though she did not show it.

'Strange. I haven't even fed him the World Tree leaf, yet his right arm came running in on its own and he recovered his strength. How did that happen?'

Wait. That healing potion that cured his right arm... Could it have...?

Hardly daring to believe it, I asked the Regressor.

"Shei. Did the ingredients for that healing potion happen to include..."

"Yeah. Earth's vital energy works well on someone like him, so I used a World Tree leaf. Why?"

I could not contain my astonishment at her nonchalant reply.

"Wow. You're only ever a big spender at times like these."

"It was the bare minimum. Someone had reduced his arm to a rag, and the curse was so severe that nothing less would have healed it."

"Yes, yes. It's all my fault."

Tsk. Clicking my tongue, I pressed close to the corner and cautiously peered into the classroom. The Regressor trailed after me, not knowing what was going on.

"The lieutenant colonel's met the undying one. Is this why you called me?"

"We're too late already. Let's just watch."

While the Regressor and I watched through the open door, the officer assessed the undying one with sharp eyes beneath the brim of her cap.

He was a massive, muscular man who looked to be two meters tall. The body visible through his tattered shirt was darker than bronze, looking more like metal than skin. His brawny frame overflowed with vitality. Though she had yet to use the World Tree leaf, he had already regained the strength of his prime.

'Still, what was that right arm that came running in earlier...?'

At any rate, all that mattered was a favorable outcome. Putting the right arm out of her mind for now, the officer looked him up and down.

'He reportedly tore a person apart with his bare hands. He may not stand out here in the bottomless pit, but he belongs to the immortal race, once known as a race of berserkers. And he held their second-highest position, the "Right Arm"... He should make a capable helper.'

The land of the undying remained a tribal society. After leaving it to wander the world, Rash had taken a great interest in the wealthy, militarily powerful Military State. Following extensive negotiations and acceptance of its stringent conditions, he had even obtained temporary citizenship so he could stay there.

Only to commit murder and be cast into the bottomless pit without a second thought.

'One of the few here who feels goodwill toward the Military State.'

In this bottomless pit full of enemies, cut off from the world, she had found the one person who might become an ally.

The officer felt an immense inward relief.

'Thank goodness I solved the bundle's riddle. If I hadn't remembered... Their instructions are always so vague...'

Having deliberated with a hand on her chin, the officer finished her cold calculations. The undying one gazed happily at the World Tree leaf and spoke with eager anticipation.

"May I truly have this?"

"Very well. However, there is a condition."

"My! Such a precious gift! Thank you!"

"I said there was a condition."

Judging that he would be useful enough, the officer pulled down the brim of her cap and spoke.

"It is not a gift. It is an expense I incurred for your benefit, trainee. It has cost me considerably, so in return, you will..."

"Haha! You people of the Military State certainly have a knack for making everything sound stiff! I shall accept this gift with the greatest joy and gratitude!"

"Trainee. As I keep telling you..."

The officer regarded him with displeasure as he kept insisting it was a gift. She thought he intended to pocket the World Tree leaf by passing it off as one.

But that was a gross underestimate of his generosity of spirit.

"No, it is a gift!"

Shaking his head stubbornly, the undying one once again thrust up his thumb.

"This is an immensely precious gift to me, and the very nourishment I needed most, short of vital energy as I am! You came to find me and deliver such a gift in person. Surely that makes it a heartfelt gift. And having exchanged such feelings, could we not call ourselves friends?"

"... What?"

Raised in the Military State and unaccustomed to such words, the officer belatedly understood his meaning.

In other words, he was refusing a financial debt in favor of a debt of gratitude.

A debt ended once it was paid, but friendship would not wither until the feelings behind it faded.

"I'm not a man who refuses a friend's request. Now, what can I do for you, my friend?"

Apparently taken aback by this turn of events, the officer fell silent for a moment, lost in thought.

But she had been driven into a corner. Now she had neither reason nor grounds to refuse.

Nor any desire to.

"... I have a task to carry out. I would like you to help me with it, trainee."

"Haha! Anything for a friend's request!"

The undying one extended his hand. Reluctant though she was, the officer eventually took it.

'... I have no wish to be friends with some prisoner trapped in the bottomless pit. But for making use of him right now, this may be better.'

Friendship or debt—it made no difference.

So long as she could make use of this undying man who did not know to value his own life, the officer decided not to concern herself with what to call their relationship.

'Perhaps it's because he's so big... His hands are large, too. His fingers alone are two joints longer than mine...'

Finding herself having an incongruous thought during their handshake, the Instructor gave a brief shake of her head and pulled herself together.

'No. I was merely considering his build. At this size, he would make a perfect meat shield.'

Good.

It was about time to withdraw. Looking away from them, I whispered into the Regressor's ear.

"Shei."

She recoiled and jumped.

"Ah, shit! You scared me. What?"

Why the overreaction? I addressed the Regressor, who was practically hissing with every hair on end.

"We're both men. Why are you so startled?"

"It's creepy! You could just talk. Why whisper?"

"I can't exactly shout when everyone inside would hear us."

"I keep our sound from escaping as a matter of course, so it's fine!"

So stalking was a passive skill for her. How admirable.

I nodded and pointed to the side.

"They look about ready to come out. Shall we run away?"

"Run away? Didn't you need something from the undying one?"

"That was taken care of a moment ago."

I glanced back at the officer, who had obtained the trusted helper she wanted, and murmured.

"I've achieved what I wanted."

The Regressor tilted her head, not understanding what I meant.

"Leaving like this doesn't sit right with me. The undying one... Him siding with the lieutenant colonel won't make any meaningful difference, but... I'd still rather avoid the nuisance."

"Oh, please. Says the world's biggest nuisance."

"What?"

"Never mind. Just come on!"

It was about time for the officer and the undying one to leave the classroom. To avoid disturbing them, I pulled the Regressor along and headed outside.