A group of five teenagers of the same blood-type 'O' become friends at art college. Prim has a crush on bad boy Art, while her friend Foon likes quiet Puen. The five form a band and survive freshman initiation rituals, but conflict erupts when romances break up the group's harmony.
| Actor | Role |
|---|---|
 Tata YoungPrim | Prim |
 Manaswee KrittanookulFoon | Foon |
 Ray MacDonaldArt | Art |
 Shahkrit YamnarmPuen | Puen |
 Sriphan ChunechomboonChomphu | Chomphu |
 Penpak SirikulPrim's Mother | Prim's Mother |
| TThamapat SeengamratFoon's Father | Foon's Father |
| TThorung JarungkijananFoon's Mother | Foon's Mother |
| PPraphot MayuraPuen's Father | Puen's Father |
 Duangdao JarujindaPuen's Mother | Puen's Mother |
| KKhomsan NanthajitKoe | Koe |
| CChayaporn BunnagAuan | Auan |
| TTharawit ChittjaiOng-art | Ong-art |
| SSiranat RatchusantiMekin | Mekin |
| CChaithat MettichavalitJeab | Jeab |
| SSoisuda KokpongNian | Nian |
| AArun WacharasawatOng-art's Father | Ong-art's Father |
| KKumaree ChinnawatOng-art's Mother | Ong-art's Mother |
 Songsit RoongnophakunsriNid | Nid |
 Duangkamol LimcharoenEditor | Editor |
| SSavitree PuthakayaPrim's Aunt | Prim's Aunt |
| VVanich CharungkitananLecturer | Lecturer |
| KKerkkrai UnsonthiDean | Dean |