On a sunny day, a boy named Jo-kang meets Ari, a girl in a yellow raincoat, and they become friends. Jo-kang falls helplessly in love with the quirky but attractive Ari, but one day, she suddenly disappears.
| Actor | Role |
|---|---|
 Kang Hye-jungA-ri | A-ri |
 Cho Seung-wooCho Jo-kang | Cho Jo-kang |
 Kang Shin-ilJo-kang's Dad | Jo-kang's Dad |
 Lee Jae-yongMonk | Monk |
 Park Shin-hyeByeon-ja | Byeon-ja |
 Jung Jin-youngDr. Chu | Dr. Chu |
 Woo HyeonTaxi driver | Taxi driver |
 Lee Hyeong-cheolDr. Kang | Dr. Kang |
 Cho RyunJo-kang's mother | Jo-kang's mother |
 Park Gun-taeYoung Jo-kang | Young Jo-kang |
| BByeon Ju-yeonYoung A-ri | Young A-ri |
 Jin KyungTeacher | Teacher |
 Chung Sung-hwaJoon-chul | Joon-chul |
| JJo Seong-wonSang-hyeok | Sang-hyeok |
 Song Young-gyuYoung-ho | Young-ho |
 Nam Jung-heeGrandmother | Grandmother |
 Kang Lee-seokKid | Kid |