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Izuku watched in wonder as a shark flitted past the submarine window, quickly snapping a photograph of the animal. Upon seeing the photo, he nearly screamed in excitement.
That's a Japanese Roughshark!
Izuku happily wrote down his findings in his journal, pencil speeding across the page in his excitement. They were such a rare species, and here he was getting to witness one in the wild!
He had seen so many incredible things during his month-long stay on the Submarine Mighty. Izuku had been so lucky to be chosen to do an internship with the captain over the summer, and he couldn't wait to tell his mom about all of the strange and bizarre creatures that he'd seen.
As he finished writing in his journal and looked back out the window, however, he saw the quick flash of something moving just in the corner of his eye.
Tentacles. Long, thick, white tentacles, with large, razor-sharp suckers covering them.
Is… is that a giant squid?
Izuku fumbled around, trying to grab his camera in order to get a good photo of the beast, but by the time he had even held it up, it had vanished. He sighed, lowering the camera, and began sketching the squid from memory instead.
Why was it white, I wonder? Was it dead? Dying? No, it wouldn't have been able to move that quickly if it had been. Albino, maybe? Is that possible in cephalopods? Or is it a new species? Man, if I missed taking a photo of an undiscovered species...
It was only a few minutes after Izuku had seen the strange tentacles that a crash rang throughout the sub, followed by the blaring of the alarms stationed throughout it and the terrified shrieking of the rest of the crew. Izuku shot up in response to the commotion, running as fast as he could towards the sources of all the noises.
"What's going on?!" He asked, shouting to be heard. One of the older members of the crew stopped, pointing a shaking hard towards the front of the submarine, where a large window was located. When Izuku looked out of it, his blood ran cold.
It was the same white tentacles he'd seen earlier, now wrapping themselves around the sub. Izuku watched in horror as the tentacles began to squeeze, forming cracks in the window. The cracks widened as the beast squeezed harder, small spurts of water beginning to trickle in, forming small puddles on the floor and causing more alarms to join the cacophony of noises.
Ohgodohogdohgod we're going to sink and I'll die and Mom isn't going to know what happened to me and she'll be left all alone and there will be nobody there for her-
A loud crunching sound sounded throughout the cabin as the beast began to target the rest of the ship. The crew watched, helpless, as the metal hull of the sub began to warp, water spilling in faster now.
The previous loud panic of the people in the cabin turned to quiet sobs as they realized that there was nothing they could do. The ship wasn't moving anymore, too broken to go on, and they were too far from the surface for anyone to come help them. They were alone. Totally isolated and unable to save themselves from the monster outside of their cabin or from the cold water now circling around their legs.
As the ship took on more water, the first tentacles breached the interior of the cabin. They pulled at the sides of the broken metal, widening the hole further, until it was large enough for a person to fit through. Water flooded the cabin, submerging the entire crew in an instant.
As they were plunged into the freezing cold water, the tentacles appeared again, dragging the crew out from the safety of the submarine into the open ocean. Izuku was pulled away from his fellow crewmates, towards whatever monster had decided to attack them.
The sunlight here was dim, barely penetrating through the water, but Izuku could still see the outline of their attacker. But rather than the mantle that Izuku had been expecting to see, the tentacles were attached to the body of what looked like a human torso, although far larger than any human ever could be, with skin a sickly white color and webbed, clawed hands. Its red eyes glowed as Izuku was brought closer and its mouth opened to reveal sharp teeth as it grinned.
A sudden, sharp pain erupted in Izuku's side. He glanced down at the area, watching as red blood spilled out of the wound. To his confusion, however, the blood began to turn purple, finally landing on a clear blue before the wound sealed up- as if it had never been there in the first place.
But though the wound was gone, the pain was not. It spiked around his legs, causing him to nearly kneel over in his agony. Izuku looked down at the source of his pains and watched in horror as four small lines began racing down each leg, splitting them apart as they went. The split off sections thinned and darked, forming new, green limbs. Smaller, sharp itching sensations began to form on each new limb as small suckers bubbled to the surface.
The pain continued, leaving Izuku to watch as nails sharpened as they turned to claws and webbing sprouted between his fingers. His skin, too, was not left unchanged, a light green tone spreading across his body as it stretched, growing larger and larger.
Throughout this all, the monster held him in his arms, coddling him and whispering words that Izuku slowly grew to understand.
"That's it, baby. Just a little longer. Hold out through the pain, it's almost over, I promise."
As the transformation finally, finally ended, Izuku's eyes began to drift shut, his body unconsciously leaning into the arms of the monster that had caused all of this, seeking comfort, falling unconscious not long after.
The monster, the kraken All for One, held his new baby gently, pleased with how well the day had gone.
He moved one of his tentacles to brush against the boy, cooing aloud when one of the small tentacles wrapped around his in response. Even when unconscious, it seemed the baby knew who his father was.
In his other tentacles, Hisashi held the dead bodies of the people from the same clam as his little pearl. They would make a fine snack for his little one once he woke up. He would surely be hungry, and All for One wanted to make sure that his little pearl grew up to be healthy and strong.
Slowly, so as to not disturb his baby, Hisashi made his way back to his cave. His little one needed a safe place to be in once he woke up, and the open ocean was no place for one as young as him.