Vodka

It's native to Lendia, and is very popular there, though it has spread to pretty much everywhere else since, particularly to Ruscovy and Alandi.
The Ruvian Church looks very harshly upon the drink, as it is seen as a lazy man's beverage, but the Lendians maintain that, as the hardest working people in Genosism, they must also relax the most when the day is over, and so their drink is good for them. Pontifatrix Lea (a Lendian herself) supposedly never touches the stuff, but the Pontifatrix Guards are famously hard drinkers, and are well supplied from the barrels sent to her from the faithful in her homeland.