The ninth episode of "Bitch X Rich" kicks off with a nostalgic flashback to a year prior, where Oh Si-eun's name was conspicuously struck off the prestigious Diamond Club roster, a casualty of her family's financial collapse. Shunned by her former peers among Cheongdam's elite six, Si-eun found herself the butt of their jests. Fury mounted within her until she lunged at one taunting classmate, only to be halted by Je-na's stinging slap across the face.
Je-na, her tone ice-cold, decreed that she wished for no further entanglement with Si-eun, urging her to maintain a respectful distance. But just as the confrontation seemed to ebb, whispers among the students shifted to gossip about Professor Ha's alleged affair with a wealthy tycoon. Seizing the moment, Si-eun retaliated, hinting darkly that Je-na's own status was precariously perched, given the rumors swirling around her father's extracurricular activities.
Flash forward to the present, where Si-eun feigns timidity as she crosses paths with Je-na. Je-na, suspicious, inquires about Si-eun's newfound camaraderie with Hye-in and her mysterious involvement with a financially struggling student. Threatening exposure, Je-na finds herself startlingly rebuffed by Si-eun, who dares to remind her of the unspoken secret – Je-na's confession regarding her brother's suicide. Adding insult to injury, Si-eun predicts Je-na's imminent downfall, revealing that her father's mistress carries his unborn child.
Meanwhile, Do-eon observes Je-na from afar, his suspicions hardening that she was behind Hae-in's misfortune. Recollections of Je-na's indifference to Hae-in's plight and his father's cautionary advice about choosing friends wisely echo in his mind. Elsewhere, Hye-in, frustrated and secluded in the art room, receives an unwelcome visit from Si-eun.
With a confession of her own, Si-eun admits to intimidating Hye-in, rationalizing that since Hye-in never witnessed the face of Hae-in's pusher, blaming Je-na was a convenient expedient. She issues an ultimatum, giving Hye-in seven days to pin the accident on Je-na or face the public release of a spy cam video. Si-eun reveals that Duk-min, their fellow Diamond Club member, had habitually recorded their private moments, and she now possesses those incriminating footage. Should Hye-in refuse to comply, Si-eun threatens to spill the videos online, dragging everyone into the scandal's spotlight.
In this tense tableau, Si-eun's manipulation and desperation weave a web of deceit that ensnares not just her adversaries but also the innocent bystanders caught in her quest for revenge.
On that fateful day, Do-eon ventured into the exclusive Diamond Club room, where he encountered Woo-jin, Yul-hee, and Je-na, gathered together. An uneasy silence loomed between Je-na and Do-eon, their words unspoken but tensions high. Announcing his intention to bring Hye-in as his guest to their gathering, Do-eon's revelation stirred a tempest of emotions within Je-na. She fumed, perplexed by Do-eon's fascination with individuals of lesser social standing, such as Hae-in and Hye-in.
A fleeting memory flashed back to a rooftop conversation between Hae-in and Je-na, predating Hae-in's misfortune. Hae-in had uncovered Professor Ha's pregnancy with Mr. Baek's child and hinted at witnessing her father's chauffeur delivering her home late at night, the narrative abruptly halting before Hae-in could unveil her ulterior motives to Je-na.
Returning to the present, Je-na visited her mother in the hospital, where nostalgia for shared joy filled the air. However, as Je-na departed, she inadvertently overheard her chauffeur whispering about shareholders reconsidering her mother's equity in light of Mr. Baek's impending parenthood.
On her journey back, Je-na stumbled upon Hye-in, tears streaming down her face on the bustling street. Halfheartedly attempting to console her, Je-na joked that tears were beneath Hye-in's fiery demeanor, reminiscing about her penchant for confrontation. Ignoring Si-eun's persistent calls, Hye-in informed Do-eon of her readiness to assist him.
The following day, Do-eon and Hye-in made their entrance into the Diamond Club room, forcing Woo-jin to depart abruptly. Their mission: to uncover Duk-min's cache of molka videos, illicit recordings he had amassed within the room. Hye-in seized a pen drive bearing Kim Hae-in's name, just as So-mang was exacting his vengeance on Duk-min, beating him into submission and compelling him to erase all traces of the videos from his cloud storage. With a chilling warning, So-mang threatened to expose Duk-min's own compromising footage should he dare to leak any of the videos online.
Triumphant, Hye-in and Do-eon exited the room, their prize a treasure trove of flash drives, each containing pieces of a puzzle that could unravel many secrets.
In the meantime, Professor Ha pays a visit to Mr. Baek, only to be astounded upon discovering Je-na's presence there. Je-na affectionately addresses Professor Ha as "Mom," causing the professor to grow flustered as she attempts to clarify her position to Mr. Baek. Sensing the awkward tension, Je-na excuses herself, leaving the pair to their amorous endeavors, hinting at a dinner date. Professor Ha, curious and intrigued, trails Je-na out of the office, puzzled by her sudden assumption of the role of the doting daughter.
Je-na reveals her true intentions, asserting that she has grown weary of waiting for someone else to claim her mother's fortune and declares her determination to thwart Professor Ha's son from ascending to the position of Hanmyeong heir in her stead. As the scene draws to a close, Hye-in finds herself transfixed by the video on Hae-in's USB drive. Her eyes widen in disbelief as she witnesses Hae-in entangling herself with Woo-jin, leaving the episode on a shocking and cliffhanger note.
