he's an alpha that's undergone the medicine to make him into a fertile omega to hold a baby & so I think maybe a side effect of the thing is causing him to give off omega pheromones but when he's not in heat maybe he just keeps his alpha pheromones
but it could also be him being ho*** to give off omega pheromones to attract a mate.
It could be his pheromones interacting with the other alphas 'mones.
he's for sure alpha but went through that process to be able to conceive a baby for the throne. That's why this may be confusing. Go back to chaps 1-
