Original Story (Spoiler Warning!!!)

Chapter 1 Ren, the protagonist, is being transported to the LTO Laboratory in the back of a lab vehicle. When he somehow escapes the truck, he happens upon Serbia High School. As Ren enters the school, the students look at him with curiosity, wondering who he is. Ren removes a prank paper from his locker and discovers the culprits were Keck, Lina, and Root. Ren considers transforming into his true form, but Meryl, Biko, 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 Merti, who aren't actually bad. Ren looks at a bulletin board with missing person posters and looks shocked. When the school bell rings, Meryl urgently grabs Ren's hand and runs to class. Meanwhile, Aepil and Bombbox try to rush into class from another door, but Sack spots Aepil and makes a sinister face. Aepil tries to flee with Bombbox but hits a dead end. Sack stabs Bombbox with a giant weapon on his arm and continues to attack Aepil, eventually dragging Aepil into a cell.

Meanwhile, in the gym, students are playing dodgeball. Biko excitedly throws a ball at Ren, but his strength is so great that Ren is knocked out cold. Meryl looks at Ren with concern while Biko looks apologetic. Keck laughs nearby, while Lina, who seems deep in thought, spots Milni watching her through the gym doors. Lina wonders how Milni can be there when she is supposed to be undergoing resurrection surgery. Lina chases Milni, and though Keck tries to ask where she's going, Lina is already in the hallway. Milni enters the electrical room with a relaxed expression. Lina enters angrily, but the room is empty except for Milni's ribbon on the floor. The moment Lina picks up the ribbon, a monsterized Root appears behind her. Later, Keck finds Lina's body in the electrical room and falls into shock. He informs Sack, who screams for everyone to call the hospital. As negative rumors about Serbia High School spread, students (except Meryl, Biko, 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. As students continue to gossip, Locke appears with a bat and silences them. The atmosphere improves when Meryl and Biko arrive, but a grim-looking Keck approaches and tells them he suspects the culprit isn't Ren, but the master of a terrifying creature urban legend. Locke excitedly says they should go meet the master of the legend. That night, Ren, Meryl, Keck, and Locke arrive at the school, but the gate is locked. Locke breaks the lock, and inside they encounter a monsterized Root. Everyone is shocked. Ren turns his arm into black spikes to attack, but Root throws him against a wall. The three scatter and flee. Root begins chasing Keck, who trips over a book. Keck sees a normal-looking Lina in front of him reaching out a hand. Keck tries to take it, but it isn't the real Lina; Keck is then torn apart by the monsterized Root.

Meanwhile, Meryl is running when Locke grabs her hand and leads her to a classroom. Root breaks down the door. Locke tries to fight but is severely injured. As Root prepares to attack Meryl, she strikes back with a bell, but just as Root lunges at her, Locke sacrifices himself. Root eats Locke's head, leaving Meryl in shock. As Root turns toward Meryl, Ren arrives, grabs her hand, and they run for the exit. Behind them, Meryl sees normal-looking versions of Locke, Keck, and Lina smiling wickedly, telling her to "Come here." Ren finds the exit and runs toward it, 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 to pursue. Shortly after, Lutino finds Keck's upper body and, realizing there is a monster, reports it to the LTO Laboratory. Sharika receives the report and realizes that Ren, who disappeared days ago, is at Serbia High School. Back at the school, Ren continues his assault on Root. Sharika arrives and meets an angry Sack and a worried Sholick. Just as Ren is about to deliver a final blow, Root escapes through a vent. Ren turns around to find Sack, Sharika, and Sholick. Ren returns to his black-and-white form with a grim expression. An angry Sharika grabs Ren and screams, "Why is a monster like you in a normal school where students learn happily! I heard rumors that students are suffering because of you!" Sholick then frantically points out the dead children. Sharika runs to them, finding them deceased (Keck's body is split, Locke is headless, and Meryl is severely mangled).

Ultimately, Ren is misunderstood and dragged back to the LTO Laboratory by Sharika. As he is loaded into the truck, he spots Root standing among a crowd in the distance. Root watches him with a sinister smile. Ren looks back with a look of 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 changes to the LTO Laboratory, where two agents bring a captured Ren to the entrance of a containment cell. They drag him in 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 for someone to let him out. Somehow, Eitlo and River sneak out of their cells and reach Ren. Ren looks touched, and Eitlo and River try to crack the door code. Eitlo looks at River for a moment and then uses River's head to smash the door open (...are they even friends?). The loud crash triggers alarms, and other agents appear. Eitlo, River, and Ren fight the agents, but then Jerry's cell opens. Jerry emerges with a wicked laugh and attacks Ren. Ren tries to dodge, but Jerry grabs him and begins to strangle him. Eitlo pushes 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 beside her, asks if she is okay. Meryl looks terrified and trembling. (At this moment, Meryl's eyes look similar to the monsterized Root and Alice's necklace symbol from FPE). The scene shifts again to show other subjects being captured by agents (Eitlo is suppressed, Jerry is hit by an attack, River is cornered). Finally, Sharika is shown looking at reports in his office. Ren crashes through the office door (property damage?), followed by other agents. Sharika looks at Ren angrily and stands up from his desk. End of Chapter 2.

Ren: Male, 15 years old, half-human half-creature (humanoid demon creature). He is kind. His main features are black bangs with white hair in the back, a pencil ornament on his head, and one black arm. He was being taken to the LTO Laboratory in a truck when he escaped and made new friends at Serbia High School, but was eventually taken back. After a meeting at the lab, it was decided he would attend school under the supervision of the teachers and return to the lab afterward. He has special abilities in one arm. His Stage 1 true form is a humanoid creature with colors (white skin, white and black hair, black and white clothing), and his Stage 2 form is a tall, black-bodied demon with yellow eyes. Despite being a demon creature, he has a kind personality. Root: Female, 15 years old. She looks innocent but is actually evil. She is the culprit behind the terrifying creature rumors and incidents, though no one knows this (except Ren and her victims). She is a human by day but transforms into a creature at night to kill students. She is an ordinary student and presumed honor student. She can summon her victims as illusions and manipulate their minds and actions to lure their friends. She seems obsessed with Ren. Meryl: Female, 15 years old. She is kind and in a relationship with Locke. An honor student at Serbia High School. She became friends with Ren and went to the school at night with Ren, Keck, and Locke to find the missing Lina. There, they encountered the monsterized Root. Ren was the sole survivor; Meryl, Keck, and Locke were killed by Root. She is currently hospitalized.

Milni: Female, timid. Wears glasses and a ponytail. Believes all school rumors and legends. Killed by Root and currently presumed to be undergoing resurrection. Biko: Male, energetic. A robot. Loves dodgeball during PE but lacks strength control. Otto: Female, lively. Popular girl, close to Meryl, in a relationship with Aepil. Keck: Male, mean. Leader of a bully group. Has a blade for one hand. Currently hospitalized. Lina: Female, mischievous. A bully wearing a cat headband. Killed by Root and currently presumed to be undergoing resurrection. Locke: Male, hot-tempered but has a strong sense of justice. In a relationship with Meryl. Currently hospitalized. Aepil: Male, inventor. Has a beloved pet 'Bomb-shaped Box' (it doesn't actually explode!). In a relationship with Otto and loves her dearly. Rosie: Female, kind. Likes Merti. Merti: 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. Both hands are human+creature hands. Kiderlino: Female, blunt. Always has gloomy thoughts.

Sack: Male, school management teacher. Catches students who cause trouble or skip class, locks them in a cell, and makes them do overdue homework for an hour. Has a giant weapon resembling scissors for one hand. Manonia: Female, kind. Nature teacher? Jock: Male, cold. Loves coffee. Attendance teacher? Lutino: Female, timid. Janitor. Has multiple arms. Manery: Female, energetic. School nurse. Boyner: Male, lively. Cafeteria chef. Wears a mask. Sholick: Male, kind. Robot? School security guard. Dodo: Female, gentle. English teacher. Oliz: Male, only face and hands are transparent. Science teacher. Sally: Female, kind. PE teacher. May: Female, energetic. Math teacher? Jortica: Male, kind. Art teacher.

Soreu: Male, timid. Former new employee at LTO Lab, explorer. Knows the truth about the lab. Merunis: Female, cold. LTO Lab employee. Litter: Male, cold and evil. CEO of LTO Laboratory. Sharika: Male, cold. LTO Lab agent. Has a giant shotgun for one hand. Shaple: Male, relaxed and evil. The only subject treated as precious at LTO Lab. Seems to enjoy bullying other subjects. Themis: Male, kind. Researcher with green bangs. Wears research goggles. Along with Soreu, he is the only kind employee. Kind to Ren, River, Eitlo, and Treener. Agents: People who take subjects to the LTO 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. Stel: Male, quiet. 15 years old. A black creature with a humanoid form and white eyes. Shurilna: Male, quiet. Ribbon human. Body made of ribbons with three masks: Joy, Sadness, and Anger. (Similar to Gangle from Digital Circus). Shoes: Male, fierce? Beast-type monster. A beast-man with two heads. Polly: Female, presumed to be full of mischief. Humanoid monster. Very tall with a long black right hand. River: Male, very mischievous. Humanoid monster with two right eyes. Currently isolated in a cell with Ren and Eitlo. Eitlo: Male, cold but presumed tsundere. A blue demon with two horns and a tail. Possesses great strength. Currently isolated with Ren and River. Treener: Male, timid. A mysterious entity wearing a gas mask. Jerry: Male, insane and evil. A doll-type monster who 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 presumed insane/evil. Looks like an angel from heaven, but their inner personality is demonic, only 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, prickly and blunt. An ordinary office worker or team leader in the city. A perfectionist who sensitively evaluates projects prepared by employees. Other miscellaneous characters (Additional FPE characters)

•Other Serbia High Students & Teachers• Claire: Female, gentle. Ordinary student, close to Engel. Engel: Male, kind. Ordinary student, close to Claire. Kevin: Male, blunt. Famous honor student. Kirby: Male, quiet. Cat beast-man. Circle: Female, energetic and a disciplinarian. Math teacher. Has a large compass for one arm. In a relationship with Compass. Obsessed with Oreos. Compass: Male, energetic. Math teacher. Circle's large compass who can transform into a weapon and attach to her arm. In a relationship with Circle. Loves KitKats. Grace: Female, serious. Principal of Serbia High School.

•LTO Laboratory Staff• Margaret: Female, blunt and cold (used to be kind). LTO Lab agent. Despite her young age, she has excellent reflexes, speed, and marksmanship. Responsible for stopping escaping subjects. She was a kind child living peacefully with her brother Marvin, but after Marvin lost his legs in an accident and they couldn't afford hospital bills, she joined the lab as an agent for him. Scotch: Female, timid but kind. Researcher in charge of documenting subject characteristics. Kind to subjects. Skell: Male, blunt but presumed tsundere. Researcher in charge of studying subjects. Phone addict. Emily: Female, lively. Staff member. Loves coffee. In charge of warehouse management.

•LTO Laboratory Subjects• Abbie: Male, blunt but quiet and tsundere. A creature with a black body, tall, with a red eye floating above 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. Said to handle fire extremely well. Claims to fear nothing, but is actually terrified of syringes. Lizzy: Female, lively. Fallen angel with black wings and a yellow-black gradient halo. Recently discovered social media and loves it so much that researchers can now study her peacefully. Bloomie: Female, fierce. Humanoid monster with sharp hands. Voted #1 'Scariest Subject' by researchers. Alice: Female, quiet and blunt. A creature with sharp black hands and tentacles on her back. Her true form is a monster.

•Forest People• Lana: Female, bright. A kind girl living in the forest. Loves playing with dolls. Misses her childhood memories with Abbie. Robbie: Male, timid. Short but 15 years old. Originally a normal student at Serbia High, but was kidnapped by Riley after entering the forest and is now locked in a dungeon. Riley: Female, Outer personality: kind and gentle / Inner personality: psychopathic yandere. Short but 15 years old. Works at a dessert cafe in the forest by day, but is a psychopath who kills people at night to use as dessert ingredients. She fell in love with Robbie (LeeFPE version) and kidnapped him, locking him in her dungeon. Obsessed with Robbie.

•Criminals• Oliver: Male, relaxed. Son of an illegal casino owner. A spy with an overwhelming record of stealing jewels. Leader of the Spy Ups group. Zip: Female, full of mischief. A spy who is good at evading traps. Has dragon wings and a tail. Member of Spy Ups. Kind to her younger brother Chip. Chip: Male, quiet. Zip's younger brother. Follows his sister. Despite his young age, he is good at evading traps like Zip. Unlike her, he lacks wings and a tail. Petunia: Female, prickly. Rabbit beast-man. A spy with great analytical skills. Loves social media. Member of Spy Ups. Ruby: Male, energetic and highly insane. A robot. Loves rainbows. Skilled with weapons. Member of Spy Ups. Tavel: Female, insane. A biker with deer antlers on her head.

•Other Characters• Marvin: Male, kind. Margaret's older brother. An honor student currently in a wheelchair due to a leg injury. Demi: Male, kind. Accountant. In a relationship with Sasha. Sasha: Female, gentle. Accountant. In a relationship with Demi.