The background of the story is in the Erengrad Empire, a fantasy world in the omegaverse.
There's Alpha, Omega, and Beta.
There are four types of ABO:
First, humans with the werewolf essence are capable of wielding magic or mastering aura for the swordsman.
Second, the beast clan, with a humanoid figure but fully beast. They are born with a really strong physique.
Third, the demon-kind, they have strong magic, are adept in swordsmanship, and are weak in physique and weak with any holy magic.
Fourth, the mixed breed; they don't have any weaknesses and are born with the strongest traits from both parents races.