Joana gets a little overheated hauling steins of beer at the tavern. So when the crowds depart, she cools down by dropping the beer and going bare.
We don't know if Joana drinks beer. She studies yoga so she may be a teetotaler. (We're titotalers ourselves.) She's a vegetarian, too. Fellow Romanian Lana Ivans says a diet rich in corn can make breasts bigger. Czech dancer Sophie Mae says that natural foods can help. There's also a theory that the hops in beer can make a girl's tits bigger.
Whatever the facts are, there's no disputing the stimulating effects of a busty beer maid or buxom bartender. You can get boob drunk in no time! Drop your hops and show Joana some props!