Higokumaru is the Twelfth Herrscher of the Previous Era: the Herrscher of Erosion.
Back when she was still human, she was murdered by the very people who feared her, and thus came to despise humanity. After her death, her Herrscher abilities awakened. She seized control of the world's entire nuclear arsenal and launched it at mankind.
Through a ceaseless campaign of erosion, humanity, at the cost of its own extinction, finally managed to seal Higokumaru within the "Black Box."
With the birth of the Herrscher of Finality, the Previous Era was completely annihilated, and the "Black Box" fell into the hands of this era's Schicksal.
It was the very same object that the Saintess Kallen had been clutching.
And now, that box had fallen into the hands of Li Zihan.
Fueled by the Honkai energy crystals that a certain someone was never short on, the Herrscher lurking within the Black Box awakened once more.
"Where… is this place?"
Within a bizarre, alien space, the malevolent beast known as Higokumaru opened her eyes.
She was a monster that could only be described as a demonic beast, her body a stark contrast of red and white, with a multitude of tails fanning out behind her. The tips of her tails, her four paws, and parts of her body were branded with flame-like crimson markings, proclaiming her extraordinary nature.
At this moment, however, this extraordinary beast wore an expression of utter bewilderment.
The reason was simple.
Everything around her was too bizarre to comprehend.
The sun that once reigned over the sky had long since vanished from this world.
In its place was a moon.
A moon that constantly cycled through its phases, from new to full and back again.
The light and shadow cast by this moon had gone haywire, overlapping like tangible objects, stacking up against the dome of the sky.
A distant, seemingly unreal river rushed onward, encircling this small world.
This was no longer the original time and space, but another world entirely.
A world completely different from the one she inhabited.
Gazing upon this strange world, Higokumaru, for a rare moment, grew hesitant. She couldn't make heads or tails of the situation.
Just as Higokumaru was hesitating, a voice reached her ears.
"Long time no see, Ling."
The address was remarkably intimate, like a close friend offering a casual greeting.
Higokumaru whipped her head around.
What met her eyes was a young man.
"Who are you?!"
It had been so long since anyone had spoken that nearly forgotten name. The fur on Higokumaru's entire vulpine body stood on end, sharp as needles.
"I'm your friend."
The young man, whose relationship with the future Ling was indeed quite good, walked naturally towards the giant fox and spoke. His tone was bright and gentle, like a friend chatting about his day.
Friend. What a beautiful word.
A flicker of reminiscence crossed the eyes of the demonic beast, who had indeed had beings called "friends" before she was chosen as a Herrscher.
But alas, that was a lifetime ago, impossibly distant from her current self.
The moment she became a Herrscher, all her friends had abandoned her. Only her sister had been willing to stand up for her.
And then—
Her sister had died.
The fox's expression turned savage. Her protruding muzzle curled back, revealing rows of bone-white fangs.
"Friend?" A deeply mocking smile spread across the fox demon's lips. "You certainly have a talent for telling jokes."
Despite her words, she did not choose to immediately turn hostile and start a fight.
Her intuition told her that this world she was in was a manifestation of the power of the man before her.
The man opposite her was strong.
Perhaps on the level of a MANTIS.
In her current, incomplete state, she was no match for him.
And so, the malevolent beast named Higokumaru held her head high, patiently engaging with the man who claimed to be her friend.
"You should know, I am a Divine Apostle, and you are a human."
"Herrschers exist to bring about the end of humanity. Our relationship is like that of a wolf and a sheep. Have you ever heard of a sheep who danced with a wolf?"
As she spoke, the power of Erosion crept silently from her claws, seeping into the ground, the river, and even the sky.
She was the Herrscher of Erosion. She could corrode anything, be it mechanical or biological.
Moreover, no one in this era knew of her ability.
Therefore, she could unleash her power to her heart's content without fear of being detected.
At this thought, a smile tugged at the corners of the fox's mouth, who was in the darkest state of her life.
Although her power was greatly diminished for some reason, eroding a part of this world was still achievable.
By using the home-field advantage and her remaining strength, killing him would not be difficult.
Once he was dead, she would use his body to resurrect herself and finally take her revenge on humanity.
What a dishonest creature.
The young man, who had noticed his Reality Marble being eroded, watched the faint black mist rise and dissipate into nothingness.
Higokumaru wanted to seize control of a portion of his Reality Marble.
However, it was a matter of no consequence.
He possessed the Divine Key that contained the complete Authority of Erosion. A Herrscher with only a fragment of that Authority was no match for a Divine Key at its zeroth-power rating, let alone one in its Overload Mode.
Therefore, he allowed the creature to have its way with his Reality Marble, making no move to stop her.
"But I still very much want to be friends with you."
Vaguely recalling a time when Ling had complained that he wasn't "yasashii" enough, the young man looked at the creature attempting to seize his world and spoke with great sincerity.
"A sheep and a wolf, overcoming their fear and predatory instincts to dance together… don't you find that romantic?"
Because his relationship with Ling in the future was decent, the young man, who didn't mind trying a gentler approach with Higokumaru, spoke with a genuine tone.
"Such a friendship... don't you think it's wonderful?"
Is this guy an idiot?
Higokumaru, whose temper was not nearly as good as it would be in five hundred years, thought to herself. She truly hadn't expected him to spout such insipid nonsense.
"Are those your last words?"
Higokumaru, having already seized control of a considerable portion of the Reality Marble, let a mocking sneer spread across her face. Unconcealed malice—hatred, disgust, ridicule—assaulted the young man like a physical wave.
"Last words?" Li Zihan's expression was a little strange.
"How pitiful. You've even forgotten how to beg for mercy." The fox's expression was savage, confident in her victory.
This was her triumph.
The currents of the air began to reverse, sharpening into blades.
The rocks underfoot twisted and warped, becoming lances.
Searing flames erupted around the fox's form, expanding rapidly as terrifying heat spread through the area.
As her voice fell, it all came crashing down on the ridiculous man.
An illiterate is an illiterate.
Watching the multiple attacks hurtling towards him, the young man thought to himself.
The power of the Emiya family's Reality Marble was time manipulation. And yet, Higokumaru was using it to blow wind and summon earth spikes.
The young man, who was an undisputed top student when it came to the Mystic Arts, sidestepped the fierce and dangerous attacks with practiced ease.
And then—
Before Higokumaru's stunned expression, a dark red longsword, golden chains, and crimson feathers materialized beside him, one after another.
"It seems you have no interest in being friends with me," the young man said to the fox, activating three Divine Keys at once. His expression was one of pure resignation.
"In that case, I have no choice."