Nun & demon horny plot of the day: several demons getting summoned and escaping the summoner's poorly drawn salt circle only to descend on the nearby monastery. The demons manage to take the older nuns out first, quickly forcing each of them into their cocks, churning them into seed. Finally outnumbering the remaining nuns two to one, they corner each of them, splitting them on their vile engorged cocks, bloating them with unholy seed before disappearing.
The once quiet pristine monastery is now a demon factory, each defiled nun massive with rowdy spawn as they go about their self-sufficient lives, only able to think about what their spawn wants, even slipping into town at night to swallow some unsuspecting people to feed their growth. As their bodies grow wide and strong to support such growth, none even consider how long it takes for demons to mature. Their forms swell bigger and bigger without a hint of stopping, their garments littered about the place in taters, unable to contain such mass, revealing leaking heavy breasts, red stretch marks and incessant movement, their habits the only remaining indication of what they once were.
Once they'd neared a size too large to waddle they congregated in a circle, unintentionally allowing the magic of their spawn to create a circuit between them, powerful enough to draw a summoning circle encompassing each of their gravid forms.
Truly the fiery pits of hell were no place for any nun, but eager spawn sows were right at home in the heat, and finally free from the holy ground of the monastery, their spawn were willing enough to be birthed, a bit overdue, but made stronger by growing in such a hostile environment. Slowly stretched by each demon spawn that forced their way out, the sows lamented the emptiness, overcome with an inescapable need for more.