"Akuyaku Reijou Level 99 - Episode 1" introduces Alicia Ehnleit, who is on her way to the Royal Academy. Along the way, she helps an ailing elderly woman and reveals her ability to use light magic, albeit at a low level. The elderly woman's daughter informs Alicia about the academy's gates closing, prompting Alicia to hurry.

At the gate, Alicia encounters Oswald Grimsarde, a first-year student, who tells her that the gates are closed and she cannot enter. Despite Alicia's pleas, Oswald remains firm about the rules. However, he points out a crumbling section of the eastern wall that students use to sneak in and out after curfew.

Alicia meets another student, William Ares, who helps her enter the academy. They accidentally fall through a roof and land on Edwin Valschein, the second prince of the Kingdom of Valschein and a friend of William. Alicia is astonished when she learns of Edwin's royal status.

The next day, during the entrance ceremony, the academy's headmaster addresses the first-year students. Alicia reflects on the events of her first day, including shattering a window, arriving late, and being assigned extra tasks as punishment. An intruder alarm in the academy leads to a chance encounter between Alicia and Edwin, who is hiding in her room from the teachers.

The story then shifts to Yumiella Dolkness, who turns out to be the main character. Yumiella has memories of her past life and is aware that she is in the world of "Light Magic and the Hero," a game she once played. She realizes she has been reborn as the hidden boss of the game, known for her high level and powerful dark magic. Yumiella recounts her journey, starting from her childhood, where she focused on leveling up and gaining power.

At the academy, she decides not to get involved with the game's main characters (see episode introduction), hoping to live a peaceful life. However, during the entrance ceremony, it is revealed that Yumiella is at level 99, shocking everyone and disrupting her plans for a quiet school life.