Episode 5 of "Friendly Rivalry" delves deeper into the narrative of Choi Gyeong's tumultuous past. It unfolds that she had perpetually occupied the runner-up position in her class, but her plight intensified upon Je-yi's arrival at her school. Unlike her previous adversaries, Je-yi was not merely an academic paragon; she was also a beacon of popularity, casting a long shadow over Choi Gyeong.
Transitioning to the contemporary timeline, Seul-gi chances upon photographs of her personal documents and confidential information about her father on Je-yi's smartphone. Stunned beyond measure, she hastily exits Je-yi's abode. However, the situation takes a sinister turn as it transpires that Je-yi had surreptitiously affixed a tracker to Seul-gi's phone.
The following day, Seul-gi earns the highest grade for her heartfelt autobiographical essay, yet she lacks the enthusiasm to share her triumph with others. Nonetheless, shortly thereafter, her essay inexplicably vanishes from her backpack. To her horror, she discovers that someone has photocopied it and circulated it among the entire class, thereby exposing her formative years spent in an orphanage.
Elsewhere, Ye-ri grapples with the financial strain of funding her harp lessons, subtly suggesting that her life may not be the idyllic picture she paints.
Meanwhile, Je-yi endeavors to halt her classmates from perusing Seul-gi's essay, but her efforts come too late. Seul-gi confronts her, revealing her awareness of the incriminating photos on her phone. The confrontation escalates dramatically when it is unveiled that Je-yi had extorted Na-ri with a video depicting her indulging in drugs, ultimately compelling Na-ri to transfer schools.
The episode culminates with Seul-gi fervently demanding answers—how did Je-yi amass such intimate knowledge about her?
