Worry not, nobody in the story nor the gameplay tries to build any cult in any form. It's just a bunch of lewd people helping a witch summon demon lords. Hence why every level starts from zero, with only a couple of units UwU
As for the demon themselves, they won't really care ruling over the mortal world, it being already a shithole.
And if I see any glimpse of a cult, worry no more, I have angels waiting to intervene and kick butts!