The King game has one rule, which is the one who holds the king card can command anyone to do anything he wishes. However it may lead to several outcomes. Some friendships will be broken, while some relationships will blossom.
Pan, who dreams of opening a café someday, applies for a part-time job at “4 Café,” co-run by Ship and Tar. He barely passes the test of making 10 lattes in five minutes, but during the interview with owner Ship, he’s asked a strange question...
Curious about Ship’s relationship with Em, Pan tries to get closer to Em but is coldly brushed off. Meanwhile, Ship wants to plan a surprise for his girlfriend’s birthday, so Pan teaches him how to make pancakes.
At the suggestion of Ship’s girlfriend, the group goes ice skating. There, Ohm sees through Pan’s feelings for Ship. That night, at her birthday party, Ship gifts her a homemade cake he prepared with Pan.
After being taken home by Ship following a game of "King’s Game," Pan is asked to become friends with Em. Though he thought it would be difficult, Em surprisingly approaches him at school the next day...
Although Pan and Em become friendly, one night while working alone, Em's behavior causes Pan to storm off. Left behind, Em becomes concerned and asks Tar for Pan’s address so he can go apologize.
Upon hearing that Pan hit Em, Ship tries to cancel his command, but Pan refuses. When Ship shows Pan around the university lab, he realizes he enjoys spending time with Pan more than with his girlfriend. Meanwhile, Em starts working at 4 Café.
Feeling distant from Ship lately, Pen offers to help reconcile the brothers. As part of the plan, they all go bowling, but Pen tells Pan to drop out of the plan. Pan, however, isn’t convinced...
After Pen tells Ship that Em sees Pan as more than a friend, Ship asks Tar to fire Em. Upset, Pan blames himself. The next day, to cheer up, Ship and Pan go to a movie together.
After Ship and Pan grow closer, Pen visits 4 Café and fires Pan, not wanting him near Ship. Pan starts working at another café, but Ship comes to bring him back.
Seeing Pan and Em getting close, Ship can’t stay calm. Meanwhile, Pen comes to see Ship. With both Pan and Em gone, 4 Café begins hiring a new barista—but the hiring process doesn’t go smoothly.