Everyone in society has their own pack. Pups are born with only their first genders (boy or girl) then they develop their second genders later (Enigma, Alpha, beta, Omega) when they turn around 5 to 7. There's only one Enigma that gets born every 30 years. Sachi is that Enigma, the Enigma that gets born then becomes the leader of the pack if the current leader passes or if the current leader is still alive then the new Enigma will become his successor and the new pack leader once the old pack leader dies.

Sachi was the successor of the old pack leader before he died and now he's the pack leader. The top of the chain. Usually the Enigma would have an Omega by now but Sachi doesn't and he's already 23. Guest is an omega and unlike the other omegas he gets treated way worse and omegas usually get treated like lower class but you see Guest is the weakest link, he's slim and fragile that he can't even find a mate because the alphas of the pack don't think he's strong enough to breed with.

It was a late night and Guest was feeling sad, he's already 20 years old and he doesn't even have a mate yet... All Guest wants is a pup and a mate... But no one wants him..., he was thinking all of these thoughts as he walked around the edge of his pack's territory, he was too immersed in his self depreciating thoughts that he didn't sense the Enigmas presence... He couldn't smell that alluring scent.. until it was too late... He bumped into the pack leader...