"Omegaverse, also known as A/B/O (an abbreviation for "alpha/beta/omega"), is a subgenre of speculative erotic fiction, and originally a subgenre of erotic slash fan fiction. Stories in the genre are premised on societies wherein humans are divided into a dominance hierarchy of dominant "alphas", neutral "betas", and submissive "omegas"."
But thanks for the info! It's far from being the worse type of fiction I know, that's a sort of relief.