My theory. The same way the Mc can't smell another alpha pheromones because he's marked I things it's the same for Chase and he doesn't remember the omega he marked so he's more sensitive as the Mc Said he wasn't this sensitive the last time he was his guard..and I also things that's why chase asked the other security guard if he was sure Josh was an beta he might be smelling a faint smelling from him an is not sure what it is. That is my theory at least
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