In a world of alphas, betas, and omegas, the Survey Corps and most of the walls have divided themselves, alphas being the dominant gender, omegas being the subservient gender, and betas, who were somewhere in between…if not worse off due to their lack of mating instincts.

In the military, being an alpha or beta meant better agility, strength, and positions. Omegas were often kept separate to prevent heats and ruts.

The system worked…until…it didn’t, which Levi would see first hand.