Episode 5 of "No Gain, No Love" kicks off with a shroud of mystery as a figure clad in a somber black suit stalks towards Ji-uk, wielding a sinister ultimatum. He demands that Ji-uk join the ranks of Kkulbee Education as a fresh recruit, threatening to unravel the truth about his past to his biological mother's family in Canada if he refuses. Cornered, Ji-uk has no choice but to acquiesce.
The following dawn, Hae-yeong's eyes widen in disbelief as she spots Ji-uk amidst the crop of new hires at work. After delivering a terse and begrudging welcome speech to the newcomers, Ji-uk manages to steer Hae-yeong aside for a heart-to-heart. He confides in her that his presence is a matter of coercion, yet he's bound by silence, unable to divulge the full truth.
Curiously, Hae-yeong's initial inquiry veers away from probing into his sudden appearance; instead, she queries why he vanished and ignored her calls. Ji-uk explains that he wanted to shield her from lies, even if it meant distancing himself. She, in turn, cautions him against revealing their pseudo-marital bond to anyone.
Elsewhere, Ja-yeon shares a meal with Ha-jun, unaware that her every move is being scrutinized by the suspicious Gyu-hyun. Aware of Ja-yeon's true colors, Gyu-hyun surreptitiously calls Ha-jun, seeking clarification on the nature of their relationship.
As part of their induction, the novice employees engage in a mini educational fair, where their performance is gauged by customers' evaluations. Hae-yeong, in a bid to shield Ji-uk from potential scrutiny, outfits him in a bee costume, tasking him with entertaining the children and thus avoiding an assessment that might lead to a transfer. However, fate has other plans as Ji-uk briefly doffs the suit for a sip of water, revealing his dashing, perspiration-glistened visage. This unforeseen revelation captivates the hearts of the mothers, securing him a string of favorable evaluations.
As the tumultuous events unfold, Hae-yeong's gaze falls upon a distressed child nearby, his tiny frame marred by bruises. Her heart sinks as she recognizes the telltale signs of abuse. Without hesitation, she snaps photographs, only to be interrupted by the boy's father, who lunges for her phone in a fit of rage. In a flash, Ji-uk intervenes, shielding Hae-yeong and embroiling all three in a chaotic scene that ultimately leads them to the police station.
Enter Kang Bit-na, the Kkulbee Corporation's lawyer, who appears seemingly out of nowhere, offering her assistance. Hae-yeong, intrigued by her timely arrival, inquires about her knowledge of their predicament, only to be met with a vague response. Undeterred, Hae-yeong persuades Bit-na to join forces in filing charges against the abusive father. Later, as Bit-na engages in a hushed phone conversation, it becomes clear that her true motive was to safeguard Ji-uk, not Hae-yeong.
Under the watchful eye of a bus stop, Hae-yeong and Ji-uk tend to each other's wounds, their bond forged in the heat of adversity. Hae-yeong confides that her experiences with foster children have honed her ability to discern the subtle cues of abuse. As she departs, the enigmatic figure from earlier appears, whisking Ji-uk away to a luxurious penthouse apartment, bestowing upon him a credit card and car keys with a smirk. Ji-uk, fueled by curiosity, dares to ask if this man could be his biological father, only to be met with a comical revelation of his infertility.
Meanwhile, Yun Tae-hyung confides in Hui-seong his desire to tie the knot, unaware of the turmoil brewing within her heart. Hae-yeong returns home, regaling her sisters with the day's events. Hui-seong, her intuition seldom wrong, declares her foreboding about the impending wedding. As night falls, the sisters share a moment on the rooftop, Hui-seong confessing her reluctance to marry Tae-hyung and presenting Hae-yeong with a gift from him—a grandiose wedding portrait depicting Hae-yeong and Ji-uk. Hae-yeong, indignant, shoves the portrait into the attic, her anger mirrored in the act. Amidst the clutter, an old photograph of her mother and Ji-uk catches her eye, a poignant reminder of days long gone.
At the Bok residence, tensions escalate as Bok Gi-ho confronts Gyu-hyun with a new contract, a chilling ultimatum that threatens his position should he tarnish the company's pristine image in any way. Jeong-a, unyielding, retaliates by proposing a waiver for Gi-ho himself, vowing his resignation if he proves to be the one to compromise the company's reputation.
Within the office walls, Hae-yeong is formally introduced to her newfound team, comprising the stoic Park Gi-won and, unexpectedly, Ji-uk. The camaraderie swiftly blossoms, coaxing Hae-yeong into joining them for an evening of team bonding over dinner.
Meanwhile, Ja-yeon's visit to the police station takes an unexpected turn when she encounters Gyu-hyun outside. Fuming, she hurls his apology letter back at him, accusing him of sending sinister threats before storming off. However, fate intervenes as Gyu-hyun narrowly escapes a truck while retrieving the scattered papers, prompting Ja-yeon's horrified scream and subsequent faint. Swiftly, he swoops in to rescue her, carrying her to safety at the hospital.
Later, at the team dinner, Hae-yeong drowns her sorrows in alcohol, her heart heavy with Ji-uk's presence. In a moment of vulnerability, she confides in him, warning that his true identity, if revealed, would transform her from a respected team leader into merely 'Someone's Wife,' unfairly burdened with his shortcomings.
As the night wears on, Ji-uk attempts to convey his genuine joy at reuniting with Hae-yeong, despite the job offer's complexities. But her exhaustion prevails, and she drifts off to sleep, unaware of his unspoken sentiments. Upon reaching her abode, they stumble upon Woo-jae, sprawled drunkenly outside her door. Ji-uk urges a call to Yi-lin, but Hae-yeong refuses, her complex emotions about Woo-jae simmering beneath the surface. As she struggles to lift him, Ji-uk, initially retreating, silently returns to lend a helping hand.
Dawn breaks, and Hae-yeong arrives at work only to be summoned by the stern Yi-lin. In a private office, Gi-won reveals his accusation of workplace harassment against Hae-yeong, having misinterpreted their conversation as bullying. Panicked, Ji-uk rushes to Hae-yeong's side, where she faces the prospect of losing her rank. In a dramatic entrance, he declares his true status, shattering the silence: he is not a victim, but Hae-yeong's husband, standing by her side through thick and thin.
