Everyone of the main cast has one severe character flaw or another.

- Kodaka is denser than lead and has a terrible sense of humor (but thinks he is good at jokes).
- Sena is a creepy stalker, booksmart, but lacking any common sense.
- Yozora's idea of how a normal relationship progresses is so backward that she keeps trying tricks to be alone with Kodaka, which always backfire on her.
- Rika is obviously a colossal pervert and has a bad case of agoraphobia (technically Ochlophobia).
- Yukimura is very, very, very confused. Probably intentionally misled by her family.
- Kobato is childish, insecure, a little dumb, and has a severe brother complex.
- Maria is a genius, but exceptionally gullible.