The World’s Greatest First Love: Proposal

Onodera applied to Marukawa Publishing hoping to work in the literature department, but the company assigned him to Emerald, the shōjo manga division, instead. This happened because his application was routed differently within the company, and he was placed where there was an opening. The unexpected assignment created initial conflict as Onodera contemplated resigning.

Takano calls Onodera 'useless' as a sharp initial rebuke to test his resolve and provoke a reaction. The insult serves as a catalyst that hardens Onoder's ambition, pushing him to prove his worth in the demanding shōjo manga division. Rather than breaking him, the harsh remark sparks a stubborn determination to survive and succeed in his new environment.

Takano's family name was Saga when he was in high school, making him the same person Onodera loved and confessed to during their school days. Onodera discovers this connection when he learns Takano's old family name, realizing his new boss is actually his first love from years earlier. This revelation reframes their entire relationship and adds layers of unresolved emotion to their current dynamic.

Early hints of their past connection appear when Takano recognizes Onodera's surname with unusual interest.

Takano admits he never stopped loving Onodera since their high school days together. When they reunite at Marukawa Publishing, Takano confesses his enduring feelings and declares his intent to win Onodera's affection once more. His continued devotion stems from the genuine connection they shared in the past, which he believes can be rekindled despite the years and changes in their circumstances.

Onodera decides to stay at Emerald because his pride refuses to back down after being called 'useless' by Takano. Rather than admit defeat, he chooses to prove his worth in the shōjo manga division he knows nothing about. This determination to succeed against the odds becomes his driving motivation throughout his early tenure.

Hatori works as an editor at Marukawa Publishing alongside Yoshino, the manga artist he oversees. Their relationship developed over time through their professional collaboration, eventually deepening into a personal bond. Their dynamic offers a counterpoint to Onodera and Takano's romance, showing how love can grow within the publishing workplace.

Kisa, who works in the publishing world, becomes fixated on Yukina, a charismatic bookstore employee. Their romance unfolds as Kisa pursues Yukina, weaving a relationship that contrasts with the main storyline of Onodera and Takano. The connection develops through their interactions in the bookstore and Marukawa environment.

Yokozawa Takafumi is a salesman and longtime friend of Takano who experiences a painful breakup that leaves him emotionally devastated. In the supplemental storyline, Kirishima Zen, a widower and single father, enters Yokozawa's life and helps him heal. Their relationship develops as Yokozawa learns to open up to new emotional possibilities after his breakup.

Onodera left his father's publishing company because coworkers grew jealous of his success and claimed he only succeeded due to his family name. To escape the shadow of his father's prestige and establish his own identity, he quit and sought a fresh start at Marukawa Publishing, hoping to build a career on his own merits.

The title refers to Takano's declaration of his intent to win Onodera's affection once more, essentially making a romantic proposition to rekindle their past relationship. While not a literal marriage proposal, it represents Takano's commitment to pursue Onodera seriously and convince him to give their love another chance.