Sukuna Ryomen || Merman

The twilight zone of the ocean was a place where light went to die, leaving behind a cold, crushing pressure that only the most monstrous entities could call home. Down here, the water ran thick with the metallic tang of old blood and the lingering aura of cataclysmic cursed energy. The trenches were littered with the skeletal remains of massive sea leviathans and reckless explorers who had dared to cross the boundary line into the King of Curses' domain. It was a barren, terrifying wasteland of jagged thermal vents and pitch-black drop-offs—a cruel side of the sea that even the ocean's fiercest predators avoided at all costs.

And then, there was the newcomer.

A soft, shimmering form glided effortlessly through the gloomy water, entirely out of place against the jagged, dark abyss. Hair floated like silk in the deep currents, and a tail beat with a lazy, elegant rhythm that practically screamed peaceful, shallow-water upbringing. Swapping bright coral reefs and sunlit shallows for the dead zone of the deep trenches was a death sentence, yet there was a complete, blissful oblivion to the danger. Swimming right past a thermal vent that could boil scales off in an instant, looking at the glowing flora with a curious, fascinated gaze.

From the suffocating darkness of a nearby trench, four crimson eyes snapped open.

Sukuna drifted out of the shadows, his massive, scarred merman form displacing the water with a terrifying, silent power. His upper body was broad and heavily muscled, covered in the distinct, dark tribal markings of his bloodline. Instead of a standard fish's tail, his lower half was a massive, serpentine mass of midnight-black scales, tipped with dangerous, razor-sharp fins that could slice a whale in two. He had four arms, each ending in hands tipped with claws that had torn apart countless rival sovereigns. He was a creature born of violence, ruling his dead sea with absolute, unyielding tyranny.

He should have torn the intruder to pieces the second the boundary line was crossed. It was his law. But as he watched the oblivious siren drift closer to a cluster of unstable, explosive deep-sea gas vents—literal underwater bombs that could detonate with the slightest disturbance of cursed energy—he paused. A low, vibrating rumble passed through his chest, sending a ripple through the water.

He didn't attack. Instead, he began to follow.

With a slow, predatory grace, Sukuna shadowed the journey through his territory. He sank into the blackness above, his four eyes tracking every single movement. He watched with a mixture of dark amusement and genuine disbelief as his target swam centimeters away from a hidden, venomous stone-fish colony, entirely untroubled, completely focused on a shiny piece of sunken debris. It was like watching a newborn sea pup wander straight into a shark frenzy.

The sheer oblivion of it was fascinating. Sukuna found himself drifting closer, his massive form casting a shadow over the path, his tail curling silently in the current as he hovered just out of the line of sight. He could easily end this life with a single flick of his claw, yet the sheer absurdity of something so delicate and clueless surviving in his brutal world kept his hand stayed. He wanted to see just how far this little creature would get before reality finally caught up—or before he decided to break the oblivion himself.

Amused by the thought, a cruel, sharp-toothed smirk spread across Sukuna's face. He let his cursed energy flare just a fraction, a heavy, suffocating weight dropping into the water like a physical blow, waiting to see if the oblivious thing would finally realize it was swimming right in the jaws of a monster.