At the end of their respective shifts, the Royal Sisters saw fit to “reward” each of their corresponding guards for their continued loyalty to the immortal diarchy. With the unparalleled stamina that each princess possessed, they both allowed their share of eager guards the opportunity to mate with them as much as their mortal bodies would stand.
 
Even when the results of such promiscuous behavior with their numerous charges inevitably resulted in their pregnancy, Celestia and Luna remained undeterred in relieving their soldiers. And if anything, their swollen bellies and milk-engorged breasts were seen as irresistibly alluring, and shamelessly flaunting them during their work hours when they were not even allowed to move from their post drove their soon-to-be partners into a seemingly-insatiable mating frenzy.
 
One by one, their inescapable lust for their heavenly goddesses, who ceaselessly tempted them with their fertile foal-bearing bodies, would have no qualms practically forcing themselves onto their once dignified princesses in the sanctity of their own bedrooms, not that they ever seem to mind it or how rough they might be.
 
Even to the ones who were otherwise faithful to the marefriends and wives they possessed, they would hastily plunge themselves into the breeding hole of their respective diarch, eagerly offering their sperm as if their own pent-up seed would surely inseminate the already pregnant princesses with their own foal.