[do re mi fa so la ti do] synopsis...

Based on the internet novel of the same title and written by Guiyeoni, Do Re Mi Fa So La Ti Do is a touching love story with bittersweet elements. Jung-won wears a funny dragon suit, while working at the amusement park, and pours soda on Eun-kyoo, because of his taunts.[3]
A short while later, Jung-won finds out that Eun-kyoo has moved into the house next to hers.[3] Eun-kyoo now threatens to tell Jung-won’s parents that she works part time at a local mart. To keep Eun-kyoo quiet, Jung-won agrees to carry his guitar for a week.
Jung-won then starts developings feelings for Eun-kyoo, who is the lead singer in a band called Do Re Mi Fa So La Ti Do. Eun-kyoo also starts to develop similar feelings for Jung-won. The two soon become a couple.[3]
With an odd twist of fate, Jung-won goes to the bands rehearsal room and meets a familiar person from her past, a boy named Hui-won.[ Their relationship makes everything make more complicated. 10 years ago, Jung-won and Hui-won were close friends, but because of a personal matter they stopped talking to each other completely. Jung-won is now surprised to learn that her ex-close friend is now best friends with her boyfriend.[3]
Hui-won admits that he still likes his bestfriend and he wants her back. Now Jung-won is torn between her friendship with Hui-won and her love of Eun-kyoo.