"I'm worried about my nieces having to wear the veil," said the soft-spoken 29-year-old.
This fear has helped propel the young mother to the far-right of the political spectrum ahead of key presidential elections Sunday — and into the arms of the hard-line National Front party.
Troin sells children's clothes at a store in Cogolin, a town of 11,000 a few miles from the jet-set resorts of the French Riviera. In 2014, Cogolin became one of a handful of communities nationwide to elect mayors from the National Front, which is also known by the acronym FN.
Troin told NBC News that it wasn't just the FN's stance on Islam and immigration that attracted her, but also the party's populist take on the economy.
But most of all, it was the party's charismatic leader, Marine Le Pen, who captured Troin's loyalty.
"She fights for women's rights against Islam," she said. "I vote because of Marine."
Troin is part of a quiet army of female National Front supporters, who could well tip the balance of the election and give the presidency to the hard-right.
An FN victory would rewrite the continent's political playbook, given the party's pledge to take France out of the European Union. Were it to win, it would not have been an easy ride for a movement that peaked in 2002 when founder Jean Mari Le Pen — Marine Le Pen's father — reached the second and final round of the presidential election.
French voters flocked to the polls in the runoff to ensure Le Pen did not win, instead electing former President Jacques Chirac with a resounding 78 percent of the vote. Most pollsters expect a similar outcome in May's second-round vote, predicting moderate voters to rally once again to shut out the FN.
But few doubt that the party's anti-immigrant and anti-establishment platform is resonating.
The Front's anti-Islamic message is especially potent in France, whose 4.7 million Muslims make up around 7.5 percent of the population. Islamist militant attacks have killed more than 230 people over two years and plunged the country into a long-term state of emergency.
This anxiety deepened on the eve of the election after a gunman ambushed three Parisian police officers on the Champs-Elysees late Thursday, killing one and wounding two others. ISIS claimed responsibility for the shooting and French President Francois Hollande said it was likely a terrorist attack.
Meanwhile, the FN's influence has spread from its heartlands along the Mediterranean coast and in the rust-belt north, into rural "forgotten" France.
Polling institute Elabe recently predicted that 22 percent of women would vote for the National Front in the first round Sunday — almost 5 percent more than in 2012.
With just days to go, polls show the race is tightening. Centrist Emmanuel Macron is edging his way ahead on 24 percent and Le Pen is a fraction behind on 22.5 percent, according to Bloomberg polling.
Just below them, hard-left candidate Jean-Luc Melenchon has enjoyed a late surge and scandal-hit conservative Francois Fillon has hung in there despite a slew of allegations that he paid thousands of euros to his British-born wife for assistance she allegedly did not provide. A third of voters remain undecided.
The FN's ability to motivate French women could be decisive. Traditionally, it has struggled to attract female voters amid accusations of sexism, racism and anti-Semitism.
In its early years under Jean-Marie Le Pen, the party advocated a traditional image of women, opposed abortion rights and developed a reputation for a macho, strongman culture.
This bias showed. The FN was far less successful at attracting women than men. During Jean-Marie Le Pen' time in charge, around 12 percent of French women supported the party compared with 17 percent of men, according to Sciences Po Cevipof, a political institute based in Paris.
Since taking over in 2011, she has softened the party's image, steering the FN away from some of its overtly anti-Semitic and racist rhetoric in an effort to broaden its electoral base. In 2015, she expelled her father after he repeated his view that the Holocaust was a "detail of history."
In the run up to the this year's election, Le Pen dropped her last name from campaign handouts, referring to herself simply as Marine.
More recently, she specifically targeted the female vote. She has published special pamphlets and a campaign video that describes her as a woman and a mother and shows her flicking through family photo albums. She has also changed the party's logo from a flame to a blue rose.
For Troin, the children's clothes seller in Cogolin, her interest in the National Front has grown with Marine Le Pen's rise. While immigration, job security and her fear of Islam remained underlying motivators, she was also attracted to the party's re-brand.
For her, the former leader "was too outspoken, too offensive. He was a Hitler-like figure," Troin said. "But Marine is different."
In the last presidential election in 2012 — the first with Marine Le Pen as leader — the party's gender gap closed to 1.5 percentage points. It's what Cevipof professor and FN expert Nonna Mayer called the "Marine Le Pen effect."
The party has long advocated clamping down on immigration and securing borders, and throughout her campaign Le Pen has consistently made the country's Muslims a target.
"In France we respect women, we don't beat them, we don't ask them to hide themselves behind a veil as if they were impure. We drink wine when we want, we can criticize religion and speak freely," she said during a rally Monday night, comments clearly aimed at Muslims.
During the rally, Le Pen pledged to suspend all visas from non-European migrants hoping to join their families in France — often code for immigrants from mainly Muslim North Africa and the Middle East.
After Thursday night's attack in Paris, she again singled out what she sees as the threat posed by Islam.
"It is a war in which there can be no retreat because all our population and all our territory are exposed," she said.
And for all her rebranding, Marine Le Pen can also fall back into the older, harsher style of messaging.
Cathy, a 50-year-old dental assistant who was shopping for groceries in Cogolin, said she was all set to vote FN but was taken aback by Le Pen's recent comments that the French were not to blame for the anti-Jewish policies of the government during the Nazi occupation in World War II.
Referring to the "Vel d'Hiv" roundup of Jews by French police in July 1942, in which nearly 13,000 were detained and deported to concentration camps, Le Pen told French radio earlier this month she thought France was "not responsible."
Cathy, who didn't want to be identified by her second name, said Le Pen's remarks had made her pause.
"Perhaps she has the same ideas as her father but they're just hidden behind good PR skills," she said. "So I'm still thinking."
"The FN is xenophobic, racist and anti-feminist," said retired teacher Mireille Escarrat. "For me it feels like the 1930s. We're going backwards."
Many of the National Front supporters interviewed by NBC News were reluctant to admit it, and others were concerned about being named.
"I don't talk politics here," a local woman said, having led the way into a backroom of her business in the town. The 60-year-old asked not to be named or for her business to be described because she felt that admitting her loyalty to the FN would damage her reputation.
"I wouldn't mind if it weren't for my business," she added, out of earshot of her customers. "But this is somewhere everyone can come whether you vote communist or for the right."
Even in this town — where 53 percent of the population voted FN in 2014 — voting Le Pen still carries a social stigma. There's no telling just how many closet female FN voters there may be.
The party's marriage of socialist economic policy and right-wing identity politics is working in the town, which sits in the FN's traditional southern heartland. With the decline of traditional industries and unemployment at 18 percent, locals worry Cogolin is being reduced to a seasonal economy dependent on rich resort communities.
Newly-converted women at the FN's regional headquarters in neighboring Sainte-Maxime said Sunday's election would be the first time they voted for the Front in a presidential race.
"We didn't vote for Jean-Marie Le Pen because he scared us," said Monique Guckert, 67, a retired shop assistant. "His ideas were too fascist, too racist. It was too much."
Even the FN mayor of Cogolin, Marc Etienne Lansade, admitted his mother would never have voted for Jean-Marie Le Pen.
"He drove her crazy," he said. "Women understand Marine Le Pen, she's divorced, she has three children, she works — she's a modern woman," he added, sitting in his second-floor office in the town hall.
Still, not all women appreciate Le Pen's message. On Monday, a topless protester carrying flowers charged the candidate during a rally northern Paris.
Le Pen does not try to make out that she is a feminist. Of her 144 manifesto pledges, only one addresses women's issues. In it, she promises to defend women's rights by fighting against Islam, implementing a plan for equal pay and combating social and job insecurity.
"She's a fake feminist," said Camille Froidevaux-Metterie, a political scientist and expert on women in politics at the University of Reims.
Asked if a Le Pen win would be a victory for women, she said that though symbolically "it would not be nothing." She said it would mean France is ready for a female president but would have elected one on a non-feminist agenda.