Go Eunchan supports her family by working two jobs: as a Taekwondo instructor and a food delivery girl. While making a delivery, she meets Choi Hangyeol, the grandson of chairwoman Bang of Dongin Foods, a company that has a thriving coffee business. Hangyeol is a smart young man, but he is fiercely independent and abhors the thought of being tied down by one career in his life. Sporting a short haircut, Eunchan looks like a guy instead of a girl. Meanwhile, Chairwoman Park Soonyoung arranges blind dates for her grandson Hangyeol to see him settle down.

Hangyeol still thinking she's a man, asks Eunchan to pretend to be his "gay lover". She agrees to only show up on his blind dates, and he must buy her clothes and any time he touches her will be extra, and he has to give her an advance payment. Desperate, he agreed. Eunchan has feelings for Hangyeol's cousin, Choi Hanseong, but then his ex-girlfriend Han Yoojoo returns and says she wants to get back together with him. Hangyeol's grandmother owns a coffee shop, and she forces him to visit it with here, and then she reveals his new assignment.

Hangyeol is forced to take over the Coffee Prince shop by his grandmother, and he enlists Eunchan's help.

It is the grand opening for Coffee Prince, but business is harder to bring in than they expected.

The Coffee Princes head out to the countryside for their first team-building retreat, but one more person learns of Eunchan's secret.

Eunchan goes on her first "date" with Hanseong. Hangyeol struggles with his unexpected feelings for Eunchan.

Still confused, Hangyeol proposes that he and Eunchan become sworn brothers.

Hangyeol and Eunchan celebrate their momentary bliss of brotherhood, but it is quickly shattered.

As the Coffee Prince Concert quickly approaches, the relationships between Eunchan and Hangyeol, and Yoojoo and Hanseong begin to fall apart.

Eunchan wishes to reveal her true identity. Yoojoo receives an offer from the States that threatens her relationship with Hanseong.

Betrayed on all sides, Hangyeol hesitates on forgiving Eunchan. Meanwhile, Yoojoo prepares to leave for New York.

Hangyeol and Eunchan enjoy the "honeymoon phase" of their relationship, despite their awareness that he might leave for the States in a month.

Eunchan is introduced to Hangyeol's family as his new girlfriend. Yoojoo tells Hanseong that she is expecting.

Yoojoo and Hanseong's wedding makes Hangyeol more anxious to marry Eunchan.

Hangyeol's grandmother is in the hospital, but that doesn't stop her from meddling in his relationship with Eunchan.

Eunchan leaves for Italy to study to become a barista for two years.