At the grand imperial ball, Celestia makes a breathtaking entrance in a scandalous, custom-designed crimson gown, instantly capturing the attention and hushed whispers of the entire court. When her arrogant fiancé, Crown Prince Damon, publicly snubs her in favor of another noblewoman, Celestia refuses to endure the humiliation. Instead of pleading or crying like her past self, she confronts him directly in front of the assembled nobility, delivering a resounding slap across his face that silences the entire ballroom. As Damon completely loses his composure and demands her immediate arrest, Celestia remains entirely unbothered, using the sudden escalation to trigger her system activation and raise her story relevance. She boldly accepts a duel of honor against his champion, the elite Aura Knight Sir Arnold Gaius, refusing to hide behind her father's protective influence. Standing empty-handed against a fully armored warrior, Celestia unleashes her newly awakened Noblesse Oblitere skill, sending the giant knight flying into a marble pillar with a single, thunderous slap that shatters the stone. This display of raw, impossible power shocks the imperial family and forces the Emperor to oversee a formal negotiation. In the private antechamber, Celestia demands the immediate and irrevocable annulment of her engagement, successfully severing her ties with the crown. Her parents stand firmly behind her, with her mother delivering polite but devastating barbs to the incensed Empress, securing a monumental political victory. This iconic reversal establishes Celestia as a dangerous wildcard in the empire, but her triumph is quickly overshadowed by the realization that she must prepare for the brutal trials of the Tower. She returns to her estate to begin a grueling training regimen under the legendary Weapons Master, unaware of the terrifying lessons he plans to impart. As she sweats and bleeds through weeks of physical conditioning, she begins to realize that surviving this world means shedding every ounce of her modern morality, leading to a dark crossroads where she must choose between her humanity and her survival. This realization looms over her as her instructor prepares a final test that will force her to cross a line of no return.

After weeks of relentless conditioning, Celestia's instructor, Jade, presents her with a horrifying final test of resolve on the estate's training grounds. Bound and hooded before her are three men: a brutal murderer, a cruel arsonist, and an innocent debt slave who was forced into servitude. Jade issues a chilling command to execute all three, warning her that the Tower does not discriminate between the innocent and the guilty and that hesitation means death. Celestia hesitates, her modern morality recoiling at the prospect of cold-blooded murder, but the threat of being deemed unready for Summit Academy forces her hand. She thrusts her spear through the first criminal, feeling the sickening squelch of flesh and bone as his life drains away. The second execution goes horribly wrong when her trembling hands cause her to miss the heart, leaving the arsonist screaming in agony until she forces herself to deliver a second, merciful strike. The true crucible arrives with the third prisoner, the trembling debt slave who has committed no crime. Despite her internal horror, Celestia realizes that surviving the Tower requires the absolute sacrifice of her moral comfort. She drives the spear deep into his chest, watching his blood pool on the stone as a dark, exhilarating thrill rises within her. This visceral experience awakens new passive skills but leaves her deeply fragmented, realizing that the system is slowly synchronizing her soul with the original villainess's dark impulses. She stands amidst the corpses with an eerie smile, fully accepting her descent into ruthlessness. This dark transformation haunts her as she travels to Summit Academy, where she must navigate a new environment filled with hostile nobles and hidden dangers, wondering if she will lose herself entirely to the system's influence before she even sets foot inside the Tower's first floor. She tries to recall her past life's name, only to find it erased by the growing synchronization, leaving her with nothing but the identity of the villainess she was meant to play. This terrifying realization drives her to seek absolute control over her destiny, setting up a complex web of business ventures and alliances to secure her position.

Entering the Tower alone, Celestia is thrust into a series of highly irregular, agonizing trials that deviate completely from the documented combat-focused path of other climbers. On the first floor, she is locked in a dark, empty stone cell for fourteen days, forced to survive on condensation and crawling insects while her body slowly cannibalizes itself. She refuses to give up, crawling across the cold stone to lick spilled water and eating raw centipedes to sustain her fragile existence. This brutal endurance trial awakens essential passive recovery skills, allowing her to transition to the second floor, which presents an endless corridor of silent, lethal arrow traps. Lacking proper defensive gear, Celestia runs through the barrage, using an artifact glove to redirect the damage until her hand is shredded to the bone and her knee is pierced. She limps to the exit, smiling manically at the thrilling gamble of survival. The fifth floor presents her with a psychological crucible, a dilapidated mansion filled with dirty, abandoned dolls that represent the souls of children left behind. Recognizing the tragic nature of the trial, Celestia gathers all ten dolls, arranges them in the kitchen, and sets the entire structure ablaze, offering them a grand, purifying pyre. This unorthodox resolution earns her clearance of the first five floors, but she emerges back into the world as a physical wreck, barely holding onto her spear as she seeks shelter at her office. She is rescued by her loyal maid, Martha, and treated by a mysterious priest named Noah, who reveals himself to be a hidden hero. As she recovers, she must prepare for the next phase of her plan, realizing that the Tower's trials are specifically tailored to test her limits and force her to grow stronger. She also must deal with her newly summoned elemental spirit, Sir Ozymandias, an incredibly arrogant pug who refuses to assist in combat but somehow possesses the power to repel other spirits. This bizarre addition to her arsenal complicates her plans for the upcoming academy exams, forcing her to find creative ways to utilize his unique presence.

As the academy prepares for the semester exams, a series of mysterious disappearances targets commoner students, spreading fear across the campus. The culprit is a desperate, mediocre noble who has turned to dark sacrificial rituals to close the gap between himself and the talented protagonist, Arthur. When Celestia's sponsored alchemist, Anna, is kidnapped to serve as the final sacrifice, Celestia immediately launches a rescue mission. Utilizing the unique tracking abilities of Beatrice Hill's bloodline eyes, she locates the hidden ritual chamber within an abandoned wing of the academy. Celestia demolishes the wall with explosives and confronts the rogue student, instantly severing his arm with her Noblesse Oblitere skill. However, the student uses the dark mana from his sacrifices to harden his flesh, resisting her spear and launching a desperate, violent counterattack. Arthur suddenly intervenes, blocking the lethal strike with his wooden sword and attempting to negotiate a peaceful surrender. Celestia, disgusted by Arthur's naive hypocrisy and unwilling to leave a dangerous enemy alive, uses hidden explosives to detonate the rogue student, ending his life in a brutal explosion. This ruthless resolution shocks Arthur and Liana, highlighting the irreconcilable divide between Celestia's pragmatic survivalism and Arthur's heroic idealism. She returns to her dormitory to prepare for the final exam, her story relevance rising significantly as she sets her sights on the dangerous World floors of the Tower. With the first arc completed and the minimum story relevance requirement raised, she must accelerate her plans to awaken her aura and secure her position, knowing that the upcoming trials will test her ability to maintain her identity while playing the role of the villainess. She also must deal with her parents' sudden desire to support the revolutionary movement, a development that threatens to disrupt the entire narrative and force her into a premature conflict with the empire's forces. She must navigate these complex political waters while preparing her recruits for the harsh realities of the Tower's cooperative floors.