Over 2,000 people surrounded a Vienna coffee house to protest at a lesbian couple being ejected for kissing.
Eva Prewein told Austrian newspapers that she gave Anastasia a "greeting kiss".
Christl Sedlar, the 60-year-old manager of the hundred-year-old Café Pruckel admitted to an "excessive" reaction but said they were "canoodling" and needed to ensure "recognised standards of behaviour".
She added: "Diversity such as this belongs in a brothel, not in a traditional coffee house."
News of the eviction soon spread on social media, leading to gay rights activists staging a protest with rainbow flags and a kiss-in.
"This is not an isolated case", said Gerd Picher, from the group To Russia with Love Austria.
"Time and again we hear of homophobic incidents in certain Viennese coffee houses where discrimination is apparently ingrained in the system," he said in a Mirror report.
— LGBTQ Nation (@lgbtqnation) January 16, 2015
Photos posted on the To Russia With Love Austria Facebook group showed slogans such as 'smash homophobia' spray painted on the walls.
"We are here to make a stand against intolerance and homophobia," Philipp Pertl, from the Rainbow Scouting Austria rights group, told reporters at the protest.
"The law needs to change. It cannot be that gay and lesbians get thrown out of a cafe or restaurant for kissing," he added.
One protester, 20-year-old student Julian Bartl, said: "Everyone should have the same rights, including to have a coffee. Vienna's cafe scene is still very conservative and traditional."
Dancer Nikoletta Korkos, 27, added: "Free love for all. It is ridiculous that this is happening in the 21st century, especially in Vienna.
"I come from Greece and Vienna is a thousand times more tolerant."
Vienna is host to many events every year for gays, bisexuals and cross-dressers from across Europe. Austrian singer and Eurovision winner Conchita Wurst has become the figurehead for the LGBT community.
Vienna's tourist agency has also criticised the café manager's actions.