1. Akari Takahashi: (The first born in the quadruplets). (MC). (15 years old). (Female).
2.Akira Takahashi: (The second born in the quadruplets). (15 years old). (Female).
3. Aoi Takahashi: (The third born in the quadruplets). (15 years old). (Female).
4. Asami Takahashi: (The fourth born in the quadruplets). (15 years old). (Female).
5. Hayami Takahashi: (The quadruplets' mother). (37 years old). (Female).
6. Hisashi Takahashi: (The quadruplets' father). (40 years old). (Male).
7. Tomo Kobayashi: (The quadruplets' classmate). (16 years old). (Male).
8. Fumiko Kobayashi: (Tomo's younger sister). (8 years old). (Female).
9. Itchika Kobayashi: (Tomo and Fumiko's mother). (38 years old). (Female).
10. Hiroshi Kobayashi: (Tomo and Fumiko's father). (42 years old). (Male).
11. Himari Tanaka: (The principal's daughter and Akari's childhood enemy). (16 years old). (Female).
12. Sanyemi Tanaka: (Himari's elder brother). (17 years old). (Male).
13. Hikaru Tanaka: (The principal). (37 years old). (Female).
14. Chiyo Rengoku: (Himari's best friend). (16 years old). (Female).
15. Hanako Sengoku: (Chiyo's friend). (16 years old). (Female).
16. Chinatsu Suzuki: (The quadruplets' best friend). (16 years old). (Female).
17. Ichiro Sasaki: (Tomo's best friend). (15 years old). (Male).
18. Hotaru Satoru: (Aoi's friend). (16 years old). (Male).
19. Haru Hara: (Himari's admirer). (16 years old). (Male).
20. Fuyuki Fukumoto: (The boy at the beach). (16 years old). (Male).