With her older brother, Ba-da, pressuring her, So-ra takes classes to prepare for the college exam; she stresses about aging; on So-ra's birthday, Ba-da suggests a Busan trip; he invites Do-hoon, her boyfriend, to join them.

So-Ra finds Sung-tae sleeping in his boxers on the couch; she screams in shock and wakes him up; after a fuss, she manages to kick him out of her place while he only wears underwear; Ba-da tries to help Ye-rin.

Ba-da hits his head on the ground and blacks out; Ye-rin finds him bleeding on the ground and takes him to the hospital.

After Ba-da lost his memory, So-ra decides to become Sung-tae's manager; she learns that Sung-tae is illiterate, so she decides to teach him the Korean alphabet.

So-ra takes Sung-tae to an agency to get him a commercial gig; the employees at the agency are busy moving into a new office, so So-ra and Sung-tae help them with the move; Sung-tae gets attracted to So-ra, who goes to all the trouble to help him.