As always, Thank you so much for reading!

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Sans, with his toothy grin saw Akainu reforming himself from the attack, his form wreathed in molten rock, rage distorting his face at the interruption.

"Welp, that's one way to get yourself a hotdog."

Akainu snarled and surged forward, the air blistering with a volley of magma fists. Sans didn't flinch. Shimmering blue bones materialized from thin air, forming a skeletal shield. The first wave of magma crashed against it, steam hissing in the air. Akainu pauses, momentarily confused. This possibly can't be a devil fruit.

Akainu whirled to find Sans perched atop the skeletal Gaster Blaster. He barely had time to register before the blast consumed him once more. His Logia form struggled to reconstitute; this was something different from guns or cannons, something sharper.

Sans, back on the ground, seemed to be swaying slightly. "Well, ain't that somethin," he rasped, the effort showing on his skeletal face, "I still have a few tricks" and Sans swung his arm to the right.

Before Akainu could respond, the world lurched. This was slightly different when Whitebeard was using his devil fruit. Suddenly, he was falling sideways and he was slammed into the asphalt.

"Thought you might like a change of scenery," Sans' grin was back, but edged with strain.

The admiral roared, magma erupting from him, but before he could regain his footing, the world tilted again. This time, he hurtled upwards, crashing into a crumbling facade before being ruthlessly yanked back down. It was a disorienting, infuriating assault on his very senses.

"Guess I've got you a little rattled, huh?"

Sans grinned wider, Skeletal blasters materialized around Akainu. The beams erupted, forcing Akainu to dodge. Akaniu melted through blaster fire, shifting to molten form when a shot got too close. However, the moment he was about to land an attack, Sans simply vanished with an echoing "nope", reappearing a few feet away from him.

"BURN!" Akainu's voice boomed, less human now, more of a force of nature. Yet, within the inferno, blue light blinked. Sans reappeared, slammed Akainu into the side of a building before teleporting away again.

The rain of molten rock came down, Sans was a shadow flickering between the impacts, his movements ragged, his trademark grin finally fading. Each teleport was slower, a chilling exhaustion spreading through his bones. He was out of time. Sans was now kneeling.

Akainu with his eyes burning, seizing the opportunity charged towards Sans to give the fatal blow but he suddenly faltered, with a sudden bone wall forming around him.

Sans grinned, kneeling on purpose to bait Akainu. However, it was also true that he was out of energy now.

Sans summoned hundreds of bones, they formed a rough cage, immobilizing the Admiral for a split second. Before Sans could fire his blaster again though, Akainu roared in defiance, the cage exploding with Akainu charging at Sans once more.

"Geez, most people would give up at this point."

Akainu grit his teeth, focusing on Observation Haki, predicting Sans' chaotic movements. Akainu could tell that this thing was becoming more fatigued with delay's getting longer between teleports. With a flicker of devastating speed, he read where Sans was going to teleport next. A magma fist bursted through Sans' ribcage. The skeleton's grin wavered as pain shot through him, delivering him a critical blow.

"Heh, guess I shoulda dodged that one."

Sans flew several hundreds of feet, slamming onto the ground. Sans was now battered and barely standing, staring at the boiling inferno. He's spent, unable to summon another bone or blaster, unable to outrun anymore.

"Welp… Guess I always figured I'd go out with a bang"

A flicker of doubt snaked through the usual apathy. He first thought of the Underground, the monsters who finally saw the surface thanks to that kid. Papyrus, Toriel, Undyne, Alphys, Asgore, and himself are also happier now with no more time and space anomalies…

(Am I having flashback? Huh, Neat)

Everyone got their happy ending, all because of a determined human with a hopeful smile. He owed it to the kid.

(*Sigh… Just this once, I guess. Might as well make it a good show, right kid?)

Akainu bellowed, the molten mass about to erupt, Suddenly, the fiery form seized. An invisible force clamping him down again, halting his expansion. Akainu strained, magma rippling across his body, but he couldn't break free.

Sans is slumped against a pile of rubble, his blue eye flickering brighter.

"Looking for something? Sorry, It's rude to stare."

With a final surge of effort, Sans lifted his skeletal hand, The gravity around Akainu intensified, crushing him towards the ground, pinning him in place. Akainu's magma body began to crack and sputter, unable to move under the relentless pressure. Akainu's body became heavy as if was being pushed down as if someone dropped a building on him.

"Think of this.. As a little payback… for the kid."

With that final, defiant act, Sans' grin widened and flipped a middle finger towards Akainu. A single, giant Gaster Blaster formed above Akainu, larger and more powerful than ever before. The air crackled with raw energy, unstable and threatening.

Sans focused the last of his determination, his will pouring into the blaster. Charging with blinding light, the beam aimed at Akainu.

"geetttttt dunked on!"

With a deafening roar, the beam erupted, consuming everything in its path.

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Smoke hung heavy in the air, the aftermath of the devastating blast. Ace was carrying Luffy, his unconscious brother cradled in his arms.

A single, crisp snapping sound cutted through the stillness. Ace glanced behind, startled, to see Sans standing nearby. The skeletal figure's usual grin seemed hollow, painted over an expression of deep sorrow.

"Hey… Can you give it to that boy when he wakes up?"

Ace blinked in confusion as Luffy's straw hat materialized in his hand.

"That kid… She kept this hat safe right up to the very end. They… Were pretty fond of that Straw Hat boy."

A choked sob escaped Ace's lip as he clutched the hat had been on Frisk's head when… He had sacrificed Luffy's .The pain of Frisk's death and all the other pirates coursed through him, a heavy mantle mingled with gratitude for their sacrifice but also guilt. He was going to live with this mistake forever.

Sans gently lifted Frisk's body, cradling it bridal style and turned around. Sans face could not be seen but there was a single drop of tear that fell. He casted a lingering glance at Ace and Luffy.

"C'mon… Let's get you home, kiddo."

With that, a swirling portal opened at Sans feet. He steps through, carrying Frisk's lifeless form, and vanished.