Yoon-Jung accidentally calls a stranger, instead of her boyfriend, and has phone sex with the unknown man. When Yoon-Jung’s relationship with her boyfriend turns sour, Yoon-Jung meets Hyun-Seung, the stranger she had phone sex with.

Na-mi, a transfer student, becomes a laughingstock on her first day of school because of her strong southern dialect. Six girls jump in to help the new kid adapt to the new environment, and the girls come to call their circle of friends “Sunny.”