Original Story (Spoiler Warning!!!)

Chapter 1 Ren, the protagonist, is being transported to the LTO Lab in the back of a lab vehicle. When he manages to escape the truck, he happens upon Serbia High School. As Ren enters the school, the students look at him with curiosity, thinking, "What is that?" or "Who is that kid?" Ren finds a prank note on his locker; the culprits turn out to be Keck, Lina, and Root. Ren considers transforming into his true form, but Meryl, Bico, and Otto arrive to give him a tour of the school facilities (Science Lab > Art Room > Playground). At the playground, a group of students who look like villains appear, making Ren nervous, but they turn out to be Locke, Rosie, and Merty, who aren't actually bad. Ren sees a bulletin board with missing person posters and looks shocked. When the bell rings, Meryl urgently grabs Ren's hand and runs to class. Meanwhile, Aphil and Bombbox try to rush into class through another door, but Sack spots Aphil. Sack wears a sinister expression, and Aphil tries to flee with Bombbox, only to hit a dead end. Sack stabs Bombbox with a giant weapon on his arm and continues to attack Aphil, eventually dragging Aphil away to a cell.

Meanwhile, in the gym, students are playing dodgeball. Bico excitedly throws a ball at Ren, but his strength is so great that Ren is knocked out cold. Meryl looks on worriedly, and Bico feels guilty. Keck laughs at the scene, but Lina, standing next to him, looks pensive. Lina spots Milni watching from between the gym doors. Since Milni is supposed to be undergoing resurrection surgery, Lina wonders who this Milni is and chases after her. Keck tries to ask where she's going, but Lina is already in the hallway. She follows Milni into the electrical room, but it's empty except for Milni's ribbon on the floor. The moment Lina picks up the ribbon, a monstrous version of Root appears behind her. Later, Keck finds Lina's body in the electrical room and falls into shock. He tells Sack, who screams for everyone to call the hospital. As negative rumors about Serbia High School spread, students (except Meryl, Bico, Keck, and Locke) start whispering that this is all Ren's fault.

Due to the rumors, Ren eats a sandwich alone at an empty table in the cafeteria while students continue to gossip. The atmosphere only quiets down when Locke arrives with a bat. Meryl and Bico join them, lightening the mood, but then a grim-faced Keck approaches. He tells them he suspects the killer isn't Ren, but likely the master of a terrifying creature legend. Locke excitedly suggests they go meet this legend. That night, Ren, Meryl, Keck, and Locke arrive at the school, but the gates are locked. Locke breaks the lock, and they enter, only to encounter a monstrous Root. Everyone is shocked. Ren transforms his arm into black spikes to attack, but Root throws him against a wall. The group scatters. Root chases Keck, who trips over a book. Keck sees a perfectly normal Lina in front of him reaching out a hand. He tries to take it, but it's an illusion; Keck is torn apart by the monstrous Root.

Meanwhile, Meryl is fleeing when Locke grabs her hand and pulls her into a classroom. Root smashes the door open. Locke tries to fight but is severely injured. As Root turns toward Meryl, Locke sacrifices himself, and Root devours his head. Meryl is traumatized. Just as Root focuses on Meryl, Ren arrives, grabs Meryl's hand, and they run for the exit. Behind them, Meryl sees Locke, Keck, and Lina looking perfectly fine but with evil smiles, beckoning her to "Come here." Ren finds the exit and runs through, but when he looks back...

Meryl has already been killed by Root. Enraged, Ren transforms into his Stage 1 true form. Root flinches in surprise and flees, with Ren teleporting in pursuit. Shortly after, Lutino finds Keck's upper body and reports a monster to the LTO Lab. Sharika receives the report and realizes Ren, who went missing days ago, is at the school. Inside, Ren continues his assault on Root. Sharika arrives at the school and meets an angry Sack and a worried Sholick. Just as Ren prepares a final blow, Root escapes through a vent. Ren turns to see Sack, Sharika, and Sholick. He returns to his monochrome human form with a grim expression. An angry Sharika grabs Ren, shouting, "Why is a monster like you in a normal school where students enjoy learning?! I heard rumors that students are suffering because of you!" Sholick then frantically points out the dead children. Sharika runs to them, finding Keck bisected, Locke decapitated, and Meryl fatally wounded.

Ultimately, Ren is misunderstood and dragged back to the LTO Lab by Sharika. As he is loaded into the truck, he spots Root standing among a crowd in the distance, watching him with a wicked smile. Ren looks on in despair as the truck doors lock and drive into the city. End of Chapter 1.

Chapter 2 After the incident, Meryl lies asleep in a hospital room with bandages on her head. The perspective shifts to Meryl's dream, where she turns around in an empty hallway to see someone. The scene cuts to the LTO Lab, where two agents bring a captured Ren to the containment area. They drag him by the arms despite his struggling. Other subjects are shown (Polly > Treener > Jerry > River). The agents throw Ren into an empty cell and lock it. Ren screams through the window, "Someone get me out of here!" Somehow, Aitlo and River sneak out of their cells and reach Ren. Ren looks touched. Aitlo tries to crack the passcode, then looks at River and uses River's head to smash the door open (...are they even friends?). The loud crash triggers alarms, and agents arrive. Aitlo, River, and Ren fight the agents, but then Jerry's cell opens. Jerry emerges with a wicked laugh and attacks Ren. Ren dodges, but Jerry grabs him by the throat. Aitlo knocks Jerry away and yells for Ren to run. Ren flees down another hallway toward the exit. The scene shifts back to Meryl's dream, where she is running through the empty hallway toward a light. Meryl wakes up in her hospital room. Her mother, sitting nearby, asks if she's okay. Meryl looks terrified, her eyes now resembling the symbol on monstrous Root and FPE Alice's necklace. The scene cuts back to the lab, showing other subjects being captured (Aitlo suppressed, Jerry hit by attacks, River cornered). Finally, Sharika is in his office looking at reports when Ren crashes through the door (property damage?), followed by agents. Sharika stands up from his desk, looking at Ren with fury. End of Chapter 2.

Ren: Male, 15 years old, half-human half-creature (humanoid demon creature). Kind-hearted. Features black bangs, white hair in back, a pencil ornament, and one black arm. Escaped an LTO truck and made friends at Serbia High School before being recaptured. Now attends school under teacher supervision but must return to the lab daily. Has arm abilities (spikes, etc.). His Stage 1 form is a colored humanoid creature (white skin, white/black hair, black/white clothes). His Stage 2 form is a tall, black-bodied demon with yellow eyes. Despite being a demon creature, he is good-natured. Root: Female, 15 years old. Appears innocent but is actually evil. The true culprit behind the terrifying creature rumors and incidents, though no one knows (except Ren and the victims). A normal student by day, she stays at school at night to transform and kill students. An honor student (presumed). She can summon illusions of her victims to manipulate and lure their friends. Seems obsessed with Ren. Meryl: Female, 15 years old. Gentle. Locke's girlfriend and an honor student at Serbia High School. Became friends with Ren. Went to the school at night with Ren, Keck, and Locke to find the missing Lina. She was killed by Root, leaving Ren as the sole survivor. Currently hospitalized (resurrected).

Milni: Female, timid, wears glasses and a ponytail. Believes all school rumors. Killed by Root, currently presumed to be undergoing resurrection. Bico: Male, energetic robot. Loves dodgeball but cannot control his strength yet. Otto: Female, energetic, popular girl. Friends with Meryl, dating Aphil. Keck: Male, mean bully leader. Has a knife for a hand. Currently hospitalized. Lina: Female, mischievous bully. Wears a cat headband. Killed by Root, presumed to be undergoing resurrection. Locke: Male, short-tempered but has a strong sense of justice. Meryl's boyfriend. Currently hospitalized. Aphil: Male, inventor. Has a pet "Bomb-shaped Box" (doesn't actually explode!). Dating Otto. Rosie: Female, kind. Likes Merty. Merty: Male, blunt. Secretly has a crush on Rosie. Soru: Female, cold. Loves music. Nimi: Female, blunt. Has cat ears and a tail. Penny: Female, energetic. Hands are a mix of human and creature. Kiderilno: Female, blunt. Always has gloomy thoughts.

Sack: Male, administrative teacher. Catches troublemakers or slackers and locks them in a cell to do overdue homework. Has a giant scissor-like weapon on one arm. Manonia: Female, gentle. Nature teacher? Joke: Male, cold. Loves coffee. Attendance teacher? Lutino: Female, timid janitor. Has multiple arms. Manneri: Female, energetic school nurse. Boyner: Male, lively cafeteria chef. Wears a mask. Sholick: Male, kind robot? School security guard. Dodo: Female, affectionate English teacher. Oliz: Male, transparent except for face and hands. Science teacher. Sally: Female, kind PE teacher. May: Female, energetic Math teacher? Jortica: Male, kind Art teacher.

Soreu: Male, timid former rookie employee. Explorer. Knows the truth about the lab. Merunis: Female, cold lab employee. Litter: Male, cold and evil CEO of LTO Lab. Sharika: Male, cold LTO agent. Has a giant shotgun for one hand. Shaple: Male, relaxed and evil. The only subject treated as royalty at the lab. Enjoys bullying other subjects. Themis: Male, kind researcher. Has green bangs and wears research goggles. Along with Soreu, he is the only kind staff member. Friendly toward Ren, River, Aitlo, and Treener. Agents: People who bring subjects to the lab or prevent them (except Shaple) from escaping. Researchers: People who manage and study the subjects.

Bwe: Male, bright? Insane? Liquid human. Very tall and bulky. Steul: Male, quiet, 15 years old. Black creature. Humanoid with a black body and white eyes. Shurilna: Male, quiet. Ribbon human. Body made of ribbons, face consists of three masks: Joy, Sadness, and Anger (similar to Gangle from Digital Circus). Shoes: Male, fierce? Beastman monster. Has two heads. Polly: Female, mischievous? Humanoid monster. Very tall with a long black right hand. River: Male, playful humanoid monster. Has two right eyes. Currently contained with Ren and Aitlo. Aitlo: Male, cold tsundere? Blue demon. Has two horns and a tail. Very strong. Currently contained with Ren and River. Treener: Male, timid mysterious entity. Wears a gas mask. Jerry: Male, insane and evil doll monster. Can manipulate needles.

Olt: Male, quiet. Wears a deer skull mask. Kills and eats anyone who enters his territory or the forest. Alma: Non-binary?, relaxed and kind but potentially insane/evil? Appears as an angel from heaven, but is actually a demon pretending to be kind.

Colling: Female, evil. White skin, long white hair. A criminal in a red and black clown outfit. Other criminals.

Sari: Female, cranky and blunt. A city office worker or team leader. Sensitive and perfectionist regarding company projects. Other FPE characters.

•Other Serbia High Students & Teachers• Claire: Female, affectionate student. Friends with Engel. Engel: Male, kind student. Friends with Claire. Kevin: Male, blunt. Famous honor student. Cubbie: Male, quiet cat beastman. Circle: Female, energetic and a disciplinarian. Math teacher. Has a large compass for an arm. Dating Compass. Obsessed with Oreos. Compass: Male, energetic Math teacher. Can transform into a large compass and attach to Circle's arm. Dating Circle. Loves KitKats. Grace: Female, serious principal of Serbia High.

•LTO Lab Staff• Margaret: Female, blunt and cold (formerly kind). LTO agent. Despite her youth, she has excellent reflexes, speed, and marksmanship. Responsible for stopping escaping subjects. She joined to pay for the medical bills of her brother Marvin, who lost his legs in an accident. Scotch: Female, timid but kind researcher. Responsible for documenting subject characteristics. Skel: Male, blunt tsundere? Researcher. Responsible for subject research. Smartphone addict. Emily: Female, energetic staff member. Loves coffee. Warehouse manager.

•LTO Lab Test Subjects• Abbie: Male, blunt but quiet tsundere creature. Black body, tall, with a red eye on his head. Sharp hands and feet. Misses a girl named Lana he met in the forest as a child. Edward: Male, evil archdemon from hell. Expert at manipulating fire. Claims to fear nothing, but is actually terrified of needles. Lizzy: Female, energetic fallen angel. Has black wings and a yellow/black gradient halo. Recently discovered social media and is obsessed with it, which helps researchers keep her quiet. Bloomie: Female, fierce humanoid monster. Has sharp hands. Voted "Scariest Subject" by researchers. Alice: Female, quiet and blunt creature. Has sharp black hands and tentacles on her back. Her true form is a monster.

•Forest Dwellers• Lana: Female, bright. A kind girl living in the forest. Loves playing with dolls. Misses her childhood memories with Abbie. Robbie: Male, timid, 15 years old despite being short. Formerly a normal student at Serbia High, but was kidnapped by Riley after entering the forest and is now in a dungeon. Riley: Female, 15 years old. Appears kind but is a psychopathic yandere. Works at a dessert cafe in the forest by day, but kills people at night to use as ingredients. Kidnapped Robbie after falling in love with him. Obsessed with Robbie.

•Criminals• Oliver: Male, relaxed. Son of an illegal casino owner. A spy with a record for stealing the most jewels. Leader of the spy group "Ups." Zip: Female, mischievous spy. Good at evading traps. Has dragon wings and a tail. Member of Ups. Kind to her younger brother Chip. Chip: Male, quiet. Zip's younger brother. Follows Zip. Good at evading traps despite his age. Unlike Zip, he has no wings or tail. Petunia: Female, cranky rabbit beastman. Spy with great analytical skills. Loves social media. Member of Ups. Ruby: Male, energetic and highly insane robot. Loves rainbows. Skilled with weapons. Member of Ups. Tavel: Female, insane biker. Has deer antlers.

•Others• Marvin: Male, kind. Margaret's older brother. An honor student currently in a wheelchair. Demi: Male, kind accountant. Dating Sasha. Sasha: Female, gentle accountant. Dating Demi.