What.

There's some notes about the omegaverse in the first chapter. It'll answer your question.

I saw some mangas say that females do have them(づ￣ ³￣)づ

I think every manga has a different concept of omegaverse. So it's important to read some notes to avoid confusion
(=・ω・=)

Ahhhh thank you so much for the explanation! (⊙…⊙ ) I'm embarrassed