Famous composer Duean Yi's newest project is to compose a love song. However, he struggles to write it; he's lost his passion. Inspiration strikes when he meets handsome barista Plengrak.
Composer Duang Yi is struggling with writer’s block after being asked by his best friend, Jangjao, to compose for the band "Winter." One day, she invites him to a café, where Duang Yi instantly falls for the charming café owner, Plengrak. Meanwhile, rumors swirl that Plengrak is dating Winter’s lead singer, Titt.
Still struggling to compose, Duang Yi frequently visits Plengrak’s café to see him but becomes curious about Plengrak and Titt’s relationship. He asks his junior, Gene, who works at the café, to investigate. Meanwhile, Winter officially signs a contract with their record label—on the condition that a trainee joins the band for one month.
After hearing from Jangjao about Plengrak and Titt’s relationship, Duang Yi is confronted by Titt. Later, Duang Yi confides in his older brother, Duang Ai, about his work and love troubles. One day, seeing Plengrak’s café overwhelmed with customers, Duang Yi jumps in to help.
Though their relationship seems to be going well, Plengrak suddenly becomes distant, leaving Duang Yi confused. Titt explains that Plengrak is simply afraid of love due to past experiences. Meanwhile, Joe instructs Duang Yi to rewrite his song again.
When Duang Yi discovers his brother secretly wants to pursue music, he asks Joe to consider teaming up with him. Meanwhile, Gene fends off a sexually harassing customer at Half Moon café. Jangjao, after rejecting a love confession from Narwa, faces awkwardness in their professional relationship.
Winter debuts with a live performance at a company showcase. Although well-received, Narwa still criticizes Jangjao. Plengrak gets upset after seeing Duang Yi give flowers to Tanwa and becomes sulky. They go out to reconcile, but Duang Yi ends up drunk, and Plengrak tenderly takes care of him.
One night, Plengrak’s ex-boyfriend, First, unexpectedly shows up in front of Duang Yi and Plengrak. Disturbed by First’s overly familiar behavior, Duang Yi leaves before hearing Plengrak’s explanation. Unable to reach Duang Yi afterward, a distracted Plengrak leaves work early—only to be visited by a worried Titt.
First confronts Duang Yi, claiming he’s still dating Plengrak. Plengrak arrives in time to drive First away. Meanwhile, Titt and Tanwa from Winter get into a fight during rehearsal, prompting Jangjao to scold them for their lack of unity. The band reflects on their beginnings to regroup.
Duang Yi receives an incredible job offer from a major company in Shanghai. Though excited, he's torn at the thought of leaving Plengrak behind. Winter’s members, shocked to hear Jangjao plans to quit the label, try to stop her. Eventually, they begin recording, bringing their dream closer to reality.
Jangjao quits and starts her own record label. As Duang Yi prepares to leave for Shanghai, Plengrak makes him a special coffee he calls "Coffee Melody." While Jangjao is out handing out flyers for her new label, Narwa appears and offers to help. He cheekily asks if, now that he’s no longer her boss, he can finally court her.