Episode 3 of "My Dearest Nemesis" kicks off with a scene where the chaebol relentlessly pesters Su-jeong. In a sudden move, Ju-yeon propels him into the pool, subsequently mislabeling her as "babe" before hastily correcting himself, asserting that it was the chaebol he had addressed. Irritated and hungry, she demands food, to which Ju-yeon reluctantly agrees, leading her to a quaint cafe. There, her attention is diverted by an adorable stuffed toy being given away as a freebie, earning her a nod of approval from Ju-yeon for her impeccable taste. He then permits her to return home.
At her abode, Su-jeong delicately attempts to peel off the expensive gown lent to her. A power outage interrupts her efforts, but she swiftly rectifies the issue, revealing her possession of an electrician's license, a skill she acquired to assist her father.
Meanwhile, at the restaurant, Shin-won educates Ultimate Pro, alias Ha-jin, on the nuances of online promotion. Their hands brush against each other, leaving both momentarily enraptured. Ha-jin apologizes, but Shin-won ponders if his attraction towards her might be mutual. Emboldened, she initiates a kiss, leading to a night of intimacy.
The next morning, Ha-jin drops Shin-won off at the market, but she stops him short from meeting her parents. On his departure, she visits her folks, who relentlessly chastise her for being a quitter. She had resigned from her job to marry her long-time lover of ten years but was left heartbroken and divorced after his infidelity. Despondent, she ventured into opening a restaurant that now teeters on the brink of closure.
Back at work, Ju-yeon, in his usual grumpy demeanor, chastises Su-jeong for failing to dry-clean the dress. Nevertheless, he privately admits his admiration for how it flattered her. During a meeting, they find themselves in unison, astonishing their colleagues.
The duo inspects the department store selected for their rebranding venture. They encounter a commotion caused by a man furious over his broken sunglasses. Ju-yeon starts to rebuke him, but Su-jeong intervenes, deploying her charm. The man calms down and purchases a new pair. As he tries them on, Ju-yeon realizes with astonishment that he is his favorite rock singer.
Su-jeong, feeling a pang of sympathy for Ju-yeon, sweetly requests an autograph and a selfie, feigning her own admiration. Grateful for the gesture, Ju-yeon expresses his hope that he wouldn't be ashamed of his hobbies anymore. Sharing a heartwarming moment, he decides to embrace life openly in her presence. He later informs Kwon of Su-jeong's exemplary work ethic, vowing never to terminate her employment. Similarly, Su-jeong sings Ju-yeon's praises to her team, leaving them astonished. As night falls, he catches her working late and, albeit abruptly, tells her to call it a day. As an afterthought, he generously allows her to keep the dress, admiring its beauty.
Back at his place, Ju-yeon meticulously prepares to store the autograph in his hidden sanctuary when Shin-won bursts in with food. However, Shin-won's mind wanders, provoked by talk of destiny. This reminds Ju-yeon poignantly of Strawberry's heartbreaking betrayal. He cautions Shin-won against falling in love, playfully chasing him when the designer teases him mercilessly.
Later, Ju-yeon visits his "sister," who has recently opened a shop. Distracted by news of his order being dispatched, his thoughts turn to Su-jeong's encouragement to embrace his passions, evoking a smile.
At Sulo restaurant, an array of flowers, a robot, and an ice sculpture arrives, a gesture from Black Dragon. Ha-jin remains unfazed, revealing herself as the "sister" Ju-yeon has been texting. Sure enough, Su-jeong arrives, upset to discover the gamers' secret correspondence, clashing with her burgeoning friendship with Ju-yeon. They bump into each other in the elevator at work, and she teases him about his smartwatch, playfully grabbing his wrist. He becomes flustered, attempting to stop her, and their gazes lock in an intimate staredown. As the elevator doors open to Kwon, Su-jeong accidentally slaps Ju-yeon in her haste to pull away.
Exiting the building, the trio stumbles upon a limited-edition pink toy, causing Ju-yeon to panic and rush home to check if his own is missing. A flashback ensues, depicting a heartbroken Ju-yeon returning home after Su-jeong's rejection. His grandmother, furious at his tardiness for his parents' memorial, is appalled by his attire and erroneously blames his toys for her son's demise. As punishment, she burns all his toys, including one gifted by his parents, leaving an indelible mark on his heart.
Currently, Ju-yeon discovers his cherished toy hidden beneath the cabinet, a weight lifting off his shoulders. With a sense of relief, he heads back to the office, only to stumble upon his team mocking the mystery owner of the misplaced toy. He labels Su-jeong a hypocrite, her assurances of not being embarrassed by one's hobbies resonating deeply with him and now feeling betrayed. He insists she retrieves the dress, unaware that she has already parted with it, placing her in a predicament. Disillusioned, Ju-yeon concludes that friendships are unnecessary as his long-awaited package arrives—a rave light that promptly malfunctions due to a defective plug. After conducting thorough research, he determines 'No1 Hardware' to be the most trustworthy option. Ironically, the store belongs to Su-jeong's father, and she reluctantly takes on the task.
As My Dearest Nemesis Episode 3 draws to a close, Ju-yeon cloaks himself in anonymity, peering from the shadows of the garage. Su-jeong approaches the entrance of the concealed room, her eyes catching the glimpse of an autograph. Simultaneously, the CCTV captures her face, alerting Ju-yeon. In a panic, he attempts to dash and intercept her, but time slips through his fingers. The secret room door creaks open,吞噬了她的身影.
