Commuters on Madrid's buses have long been banned from putting their feet on seats or smoking, but from this week a new prohibition is in place, targeting male passengers: no "manspreading".
The practice of men sitting in public transport with their legs wide apart, taking up more than one seat, has long been an irritant and the term "manspreading" appeared in 2014 in New York following a campaign against it there.
In Madrid, buses have since Thursday been kitted out with stickers banning the habit, which appears next to signs telling passengers to use their phones in moderation and keep things tidy.
The anti-manspreading pictogramme shows a man sitting with his legs and arms out wide on blue seats, a red bar sign cutting across.
"Respect other people's space," it reads.
The stickers are due to be rolled out in 2,000 buses belonging to Madrid's Municipal Transport Company.
Melisa Garcia, a 30-year-old from Madrid, thinks it's a good idea.
"It's a total lack of respect and education," she says, adding the last time her neighbor manspread on the seat next to her, she "kicked him".
"I told him: 'the seat you have is big enough for you'."
The sticker comes as the campaign #MadridSinManspreading ("Madrid Without Manspreading") rages on Twitter, launched by the "Women Fighting" feminist collective.
"It's not a question of bad education but that we women have been taught to sit with our legs closed -- as if we had to hold something between our knees," the collective writes in an online petition on Change.org that has garnered close to 700 signatures.
It adds that men, on the other hand, "have been given a sense of hierarchy and territoriality, as if the space belonged to them."
Robert Durou, a 75-year-old retiree, backed the campaign.
"Before... people were more respectful of others," he lamented.
David Correa Clares, meanwhile, admitted he has been guilty of manspreading in the past.
"People have at times told me it bothered them and I sat respectfully and that was it... But I don't think you need a rule or a pictogramme to say 'you must sit in this way'," the 19-year-old said.
That's what the conservatives who lead the Madrid region -- and manage the subway -- think, estimating that the rules of "one seat per person" are clear enough.