A dark aura mingled with Ophis' energy, boiling violently, making the air around them tremble.
The ground cracked, the already fragile buildings shook, and the spiritual pressure pressed down on anyone standing too close.
The Knight Killer blade embedded in Katerea's thigh was thrown aside as if repelled by the foreign energy now protecting her body.
The wound that had seemed severe gradually closed, regeneration accelerated by Ophis' power.
Katerea's hair whipped wildly, her eyes glowing purple with dark flashes.
An arrogant smile spread across her face. "Behold! This is the power of a true Leviathan blessed by Ophis-sama!"
With a single swing of her staff, a massive magic circle appeared.
From it, waves of dark purple snakes erupted, raging toward Rian's position.
Still wearing a faint smile and without moving an inch, Rian increased the output of Infinity.
As a result, the approaching waves of dark purple snakes seemed to freeze in midair, trapped within the Infinite Array that could not be breached by any means.
"What!?" Katerea shouted, eyes widening. "Barrier magic? No… there's no magic circle, no fluctuation in aura!"
Her eyes grew even wider as she suddenly sensed something—an aura faint, yet strangely familiar.
"W-what… what is this...? Wait… this aura…? Ophis-sama!?"
Katerea's body shivered with fear. Just moments ago, with a slight focus of thought, Rian had activated the Title: Beloved by Infinity, replacing the previously equipped Title: Sparkle.
"N-no… this can't be!" Katerea shook her head, trying to deny her own fear. "The aura… it's just similar! You're not Ophis-sama!"
With her anger surging, Katerea wildly swung her staff again, slicing through the air.
Magic circles erupted one after another around her in rapid succession.
From there, wave after wave of dark purple snakes surged forward again, this time far more numerous, striking mercilessly toward Rian.
The ground around him shattered into pieces, thick dust rising high to obscure the view.
Even the gymnasium behind him collapsed, consumed by the rampaging waves of dark purple snakes that showed no sign of stopping.
"Hahahahaha!"
Katerea laughed loudly, pride swelling as she watched the destruction unfold.
"Be grateful, human! You've forced me to unleash this much power!"
Yet, amid the chaos, a faint image of Rian could be seen standing upright, unmoved, as if entirely unaffected by the onslaught of magic.
On his fingers, Infinity briefly glowed with the cosmic blue energy characteristic of the Space Stone.
At the same time, Rian focused his mind, controlling the Blue he had previously conjured from afar, which had not yet dissipated.
At the same time, the waves of dark purple snakes suddenly froze midair, as if bound by some invisible force.
A satisfied smile spread across Katerea's face. The dust began to settle, revealing Rian completely unharmed.
"What—"
Before she could finish, a sharp whistling sound came from behind.
The Maximum Output Blue sphere shot forward at incredible speed, striking Katerea's body directly.
"GAHHH!" Katerea screamed in pain.
In the next instant, her body seemed twisted and compressed by the space itself, as if being pulled toward an unseen point of convergence, dragging everything around it along.
Even so, Katerea was not yet defeated.
Her pure-blooded devil body, strengthened by Ophis' blessing, still held, though severe wounds were beginning to appear across her form.
"Outrageous…! How dare you attack me from behind! You lowly human!"
Insults, groans, and screams of pain poured from Katerea's mouth as her body continued to twist under the pull of space.
"Oh?" Rian replied casually, taking a single step forward. "Aren't you the lowly one? Tell me, who attacked during the Three Factions meeting?"
"Shut your mouth!!" Katerea yelled, fury blazing.
She tried to muster all her magical aura, the spell already amplified by Ophis' blessing, in a desperate attempt to free herself. But her efforts were in vain.
The spatial pull intensified, squeezing her body ever tighter.
Rian slowly removed his glasses, his gaze cold. His voice was low, yet every word resonated with overwhelming power:
"Phase."
"Twilight."
"Eye of Wisdom."
The moment he spoke these three incantations, the Maximum Output Blue surged drastically, coinciding with the glowing of the Infinity Ring and the Ophis fang necklace around his neck.
The space around them warped to an extreme degree—air, dust, even fragments of distant buildings were drawn into the point of convergence.
"AAARRRGHHH!" Katerea's scream erupted, full of pain and despair.
Wild magical aura raged from her body, yet it was all devoured by the infinite power of Blue.
BOOM!
Katerea's body could no longer endure. In an instant, she exploded—blood and flesh scattered—only to be pulled back into the vortex of Blue until nothing remained.
A sudden silence fell.
Only the sound of the spatial pull roared on, gradually fading, leaving total devastation in its wake along with the dissipating Blue.
Elsewhere, after Maximum Output: Blue slowly slipped from Rian's control, the observers' expressions varied.
Sirzechs stared at Rian with eyes far more serious than usual. The diplomatic smile that always graced his face had vanished.
"…To destroy a pure-blooded devil like Katerea with a single move," Sirzechs murmured, "this is the first time I've seen something like it."
Serafall, usually cheerful, stood frozen. Her face was pale, lips trembling slightly.
"That's not the power of an ordinary human."
Her gaze fixed on Rian—not just in shock, but laced with awe and concern. Yet, her determination to match Sona with Rian only grew stronger.
Elsewhere, Azazel let out a long sigh, one hand rubbing the back of his neck.
"…Hahaha." A small, hollow laugh escaped, devoid of any joy. "Damn, this is truly insane. I knew the kid was dangerous, but… his level of 'danger' is far beyond what I expected."
He shook his head slowly, his crooked smile feeling more like a shield than sincerity.
"Katerea was arrogant beyond measure, but to be erased completely… Rian, he truly is… a monster."
Michael, on the other hand, looked at Rian with a calm and gentle expression, yet his eyes were heavy and full of meaning.
"That power… I hope Rian does not walk the wrong path in the future."
Meanwhile, Issei, Rias, Koneko, Irina, Xenovia, Gasper, Sona, Tsubaki, and Akeno could only remain frozen in their places. Their eyes were filled with shock, mixed with a sense of awe.
Should they feel grateful that someone like Rian was on their side… or should they be afraid?
Yet, that feeling was not theirs alone. The remaining members of the Khaos Brigade, and even the forces of the Three Factions, stood silent.
Their gazes were unanimous: terrified, as if witnessing something beyond the limits of normal.
Suddenly, the protective magic covering Kuoh Academy cracked and then shattered, consumed by the blazing cosmic purple fire—the unmistakable signature of Alice wielding her Power Stone.
Without hesitation, Rian shot forward at incredible speed, leaving Kuoh Academy behind along with everyone still frozen in place.
He moved so fast because, amid the stunned silence that had gripped the battlefield, Ophis' telepathic voice suddenly echoed in his mind, urging him to come immediately.
And more than anything, his curiosity about what Ophis wanted now outweighed everything else.
***
Unnoticed, two days had passed.
Tonight—or rather, in just a few minutes—Rian would disappear from the DxD world and return to the Infinity Room.
Two days ago, events nearly identical to the original timeline had occurred.
First, after Rian's departure, Vali suddenly attacked Azazel while also revealing his Lucifer lineage, before eventually clashing with Issei.
Since Vali had not fully recovered from the aftereffects of Infinity Void and the injuries he sustained while fighting Azazel, Issei managed to defeat him.
Although part of Issei's victory came thanks to his "Oppai power," Rian could only shake his head at it.
More importantly, following that incident, negotiations among the Three Factions became even stronger.
Azazel was appointed as Rias' mentor and the overseer of her Peerage.
Under Sirzechs' orders, Rias' Peerage was relocated to Issei's residence.
There was, however, a slight difference from the original timeline: Akeno and Koneko chose to stay with Rian.
That decision was not seen as a mistake by Sirzechs. With one or both of Rias' subordinates close to Rian, at least there was reasonable oversight.
More importantly, the decision was quite advantageous if someone as powerful as Rian was on their side.
But set all that aside for now.
At this moment, Koneko was spending time with Rian, having learned that he would be leaving soon, just like before—to a very distant place.
The two of them sat atop the Galaxy Lake Mansion roof, sharing a blanket, gazing at the nighttime view of Kuoh Academy.
"Senpai…" Koneko whispered softly, her voice barely audible, "I really can't come with you?"
Rian closed his eyes for a moment. His voice sounded heavy as he replied, "I'm sorry, Shironeko. You can't come, and there's no way."