The Girl with Unruly Trion
Public Story

The Girl with Unruly Trion

The sterile scent of antiseptic hung heavy in the air as Chika navigated the labyrinthine corridors of Border HQ. At eleven years old, the enormity of the facility still intimidated her, a stark contrast to the quiet life she led outside its walls.

Dropic
AuthorDropic
Created5. February 2026
Chapters25

Story context

World description

'World Trigger' anime is a modern Earth similar to present-day Japan, altered by the arrival of 'Neighbors', beings from other dimensions. Their invasion begins when a gate opens in Mikado City, introducing advanced technology and weapons unknown to Earth. To defend humanity, the organization 'Border' is created. Border uses Neighbor technology powered by 'Trion', an energy produced by the human body, allowing agents to fight ...

Initial situation

11 years old Chika Amatori is apply to be Border Agent secretly from Osamu Mikumo. She enters Border HQ.

Objective

Osamu find out Chika is Border Agent for a year, when he applied to be one. Chika aims become strong, not care about ranks. Chika want to be part of Tamakoma Branch. Chika become 13 years old, Osamu's first meet Yuma Kuga in school. Fight off Neighbor invasion. Rank War tournament. Border aims to launch expeditions to Neighbor worlds to gather intelligence and rescue abducted humans; required to become A-rank for it.

Chapter samples

1
Chapter 1
Tap to expand and read the excerpt

The sterile scent of antiseptic hung heavy in the air as Chika navigated the labyrinthine corridors of Border HQ. At eleven years old, the enormity of the facility still intimidated her, a stark contrast to the quiet life she led outside its walls. She tugged at the oversized Border uniform, the fabric stiff and unfamiliar against her ski...

The sterile scent of antiseptic hung heavy in the air as Chika navigated the labyrinthine corridors of Border HQ. At eleven years old, the enormity of the facility still intimidated her, a stark contrast to the quiet life she led outside its walls. She tugged at the oversized Border uniform, the fabric stiff and unfamiliar against her skin. A year. It had been a year since she'd secretly applied, a year of training, a year lived in the shadow of Osamu's oblivious concern. Each footstep echoed her secret. Osamu Mikumo would never approve. He’d fuss and fret about the danger, about her safety. But Chika knew, with a certainty that burned deep within her, that she had to do this. She had to become stronger. The image of her brother, his face blurred by the passage of time and grief, flickered in her mind. His disappearance, the void it left in her life, fueled her determination. Border offered her a path, a purpose. It wasn’t about rank, not for her. It was about protecting others, about ensuring no one else suffered the same loss. She paused before a reinforced steel door, the sign above it designating it as Training Room 7. Taking a deep breath, she swiped her agent ID card, the lock clicking open with a soft thud. Inside, the room was a blank canvas of white, ready to be painted with the simulated realities of Border’s training program. Yuichi Jin stood waiting, leaning casually against a wall, his perpetual smirk in place. "Amatori," he greeted, his voice laced with amusement. "Right on time. Impressive, considering you're juggling this with… other responsibilities." Chika bristled, her cheeks flushing. Jin knew. Of course, he knew. With his Side Effect, he probably knew everything. "I can handle it," she said, her voice barely a whisper. "Never doubted it," Jin chuckled, pushing himself off the wall. "But don't think that means I'll go easy on you. Today, we're working on spatial awareness. Let's see if you can keep up." As Jin activated the training program, the white room dissolved into a chaotic cityscape, complete with crumbling buildings and the ominous wail of emergency sirens. Her heart pounded, but Chika focused, channeling her fear into determination. She wouldn't let Osamu's disapproval, or Jin's knowing glances, hold her back. She had a promise to keep, a future to forge, and a strength to find within herself. But how long could she keep straddling these two worlds? The quiet, ordinary life with Osamu, and the dangerous, exhilarating world of Border? The weight of her secret pressed down on her. The day was coming, she knew, when Osamu would discover the truth.

2
Chapter 2
Tap to expand and read the excerpt

The cityscape flickers around Chika, buildings materializing and dissolving as Jin manipulates the simulation. He doesn't offer any instruction, only watches with that unnerving knowing in his eyes. A Neighbor suddenly bursts through a nearby wall, its grotesque form a tangle of limbs and jagged edges. It's a low-level one, thankfully, bu...

The cityscape flickers around Chika, buildings materializing and dissolving as Jin manipulates the simulation. He doesn't offer any instruction, only watches with that unnerving knowing in his eyes. A Neighbor suddenly bursts through a nearby wall, its grotesque form a tangle of limbs and jagged edges. It's a low-level one, thankfully, but the surprise still makes Chika stumble. "Focus, Amatori," Jin calls out, his tone light but firm. "Spatial awareness isn't just about knowing where things are, it's about anticipating where they'll be." She nods, heart still pounding, and activates her Trigger. A simple rifle appears in her hands, its sleek design familiar and comforting. She takes a breath, trying to calm her racing pulse, and focuses on the Neighbor's movements. It's clumsy, predictable. She calculates its trajectory, anticipates its next attack, and fires. A clean shot, right through its Trion organ. The Neighbor dissolves into motes of light, disappearing as quickly as it appeared. "Good," Jin says, a hint of approval in his voice. "But that was too slow. In a real battle, that hesitation could be fatal." He increases the difficulty, and the cityscape shifts again. Now, there are multiple Neighbors, darting through the streets, flanking her from all sides. The air crackles with energy as they unleash their attacks. Chika ducks behind a crumbling wall, the impact of a blast shaking the debris around her. This is different. This is overwhelming. Panic threatens to consume her, but she forces it down. She closes her eyes for a moment, focusing on her breathing, on the feel of the rifle in her hands. She remembers Jin's words: anticipate. She visualizes the battlefield, the movements of the Neighbors, the angles of attack. It's like a complex equation, a puzzle she needs to solve. When she opens her eyes, the chaos seems to sharpen into clarity. She moves, fluid and precise, using her gymnastics training to navigate the treacherous terrain. She fires, each shot calculated, each movement deliberate. Neighbors fall, one by one, until the cityscape is silent once more. Sweat trickles down her forehead, her muscles ache, but she stands tall, her rifle steady in her hands. She looks at Jin, awaiting his judgment. But then the lights in the training room flicker. A loud siren suddenly blares and an announcement booms over the loudspeakers. "All Border Agents to defensive positions. Large-scale Neighbor invasion detected in the city center."

3
Chapter 3
Tap to expand and read the excerpt

Jin's expression hardens, the earlier amusement vanishing. "Seems our little game is over. This is real, Amatori. All simulations are cancelled." He strides towards the exit, his footsteps echoing in the sudden silence. Chika watches him go, her mind racing. A real invasion? In the city center? That's where her school is, where Osamu and...

Jin's expression hardens, the earlier amusement vanishing. "Seems our little game is over. This is real, Amatori. All simulations are cancelled." He strides towards the exit, his footsteps echoing in the sudden silence. Chika watches him go, her mind racing. A real invasion? In the city center? That's where her school is, where Osamu and Yuma are. "Wait!" she calls out, but Jin is already gone. She hesitates for a moment, torn between following him and rushing to the aid of her friends. Her instincts scream at her to protect them, to shield them from the danger. But she's also a Border Agent now, with a responsibility to defend the city. Taking a deep breath, she makes her decision. She activates her comms, her voice trembling slightly as she speaks. "Amatori Chika, Border Agent, requesting deployment orders." A gruff voice responds almost immediately. "Amatori, you're assigned to Sector C, near the shopping district. Reinforce the defense line. And Amatori... try to stay alive." She acknowledges the order and sprints out of the training room, her rifle clutched tightly in her hands. The corridors of Border HQ are a blur of activity, agents rushing in every direction, their faces grim and determined. The air is thick with tension, with the scent of ozone and fear. As she reaches the main hangar, she sees several transport ships already lifting off, heading towards the city. She quickly boards the next available one, strapping herself into a seat. The engines roar to life, and the ship lurches forward, accelerating towards the open sky. Looking out the window, she sees the city spread out below her, a familiar landscape now tainted by the shadow of impending danger. Dark clouds gather on the horizon, and strange, swirling portals begin to open in the sky, disgorging hordes of grotesque Neighbors. It's a scene straight out of a nightmare, a terrifying glimpse into the horrors that await them. Her hands tighten on her rifle, her knuckles white. This is it, she realizes. This is the real test. A voice cuts through her thoughts. "Amatori, we're approaching Sector C. Prepare for drop-off."

Read more
Go to Top