The twangy guitar picking begins and the crowd cheers. It’s time for “Love Story,” the ninth song on Taylor Swift’s Eras tour set list. Onstage, Ms. Swift strums her guitar and sings a modified Romeo and Juliet story, one with a happy ending that closes with Romeo on bended knee and Juliet picking out a wedding dress.

It’s a Swift classic that has taken on a new and literal meaning during the Eras tour, where some fans have used the musical moment to underscore their own love stories with meticulously planned marriage proposals right there in the stadium while Ms. Swift performs.

Megan Voo and Justin Chong are two such fans. The couple, who live in Melbourne, Australia, and met as architecture students at the Royal Melbourne Institute of Technology in 2017, got engaged during one of Ms. Swift’s shows in their hometown earlier this year.

Ms. Voo, 26, was in complete shock when Mr. Chong, also 26, popped the question in February, mostly because she had no idea he was even at the concert in the first place. Ms. Voo attended with her sister, but, unbeknown to her, Mr. Chong had purchased a nearby seat to surprise her. (Ms. Voo’s sister was also in on the plan.)

Mr. Chong got to the concert early and made the people seated around him aware of his plan. They helped form a human shield to keep him hidden from Ms. Voo. When the moment came, they kindly stepped out of the way so he could make his way to Ms. Voo’s seat.

“When I dropped down and said, ‘Will you marry me?’ the first thing she said was ‘how did you get a ticket?,’” Mr. Chong said. He wore a ruffled shirt as a nod to the outfit Romeo wears in the “Love Story” music video and proposed with a ring from his mother.

And while the couple didn’t capture Ms. Swift’s attention, a number of nearby attendees filmed the proposal and several shared it on social media where it quickly went viral. “My friend congratulated us, saying ‘I saw your video.’ We hadn’t even announced! This was maybe two hours after the concert,” Ms. Voo said.

After the proposal, Mr. Chong didn’t return to his original seat. “I did ask everyone else. I said, ‘is it OK if I stay here with my fiancée?’” Everyone was standing for most of the show anyway, he added.

Brittany Litzenberger, 27, had a slight suspicion her boyfriend of nearly two years, Sloan Thomas, might propose at the Eras tour. While making friendship bracelets — Swifties trade them during shows — at a party at a friend’s apartment before the concert, she saw Mr. Thomas sneakily hand one off to her best friend who would be attending the show with them.

“He had sent me a few videos of people getting engaged at Eras and I was like, ‘oh, that’s so sweet. That would be like my dream,’” Ms. Litzenberger, a behavioral technician who lives in Kansas City, Mo, said.

Last July at the Arrowhead Stadium in Kansas City, Ms. Litzenberger wore a purple sequined dress, which turned out to be the perfect outfit for what was about to happen.

“Love Story” came and went without Mr. Thomas proposing. But a few songs later, during Ms. Swift’s “Speak Now” set, the proposal happened. Ms. Swift took the stage in a purple dress and began to play “Enchanted,” a love song about meeting someone for the very first time. Around the first chorus, Mr. Thomas tapped Ms. Litzenberger on the shoulder and handed her the mysterious friendship bracelet.

Mr. Thomas’ song choice was particularly meaningful, Ms. Litzenberger said. “After our first date, I got in my car and plugged in my Spotify and shuffled my Taylor and ‘Enchanted’ played,” she said.

“The friendship bracelet that he gave me said, ‘marry me,’” Ms. Litzenberger said. “Then I turn around and he’s down. He got a purple ring box. She was singing in the background, the chorus, which was just perfect timing. Everybody around me is screaming. I’m crying.”

She had a hard time focusing on the next few songs, she said. “But in a good way, you know, it made everything really exciting.” (Ms. Litzenberger’s friend who hosted the bracelet making party also got engaged during the concert.)

Carmen Castillo also said she could not remember the song that played after her now-fiancé, Vernon Chamorro, proposed during “Love Story.”

“He later told me he was afraid to propose at the Eras tour because he was afraid I was going to die of a heart attack because of all the emotions and excitement,” she said. The couple, who live in Barcelona, Spain, traveled to Tampa, Fla., in April 2023 to see Ms. Swift perform.

Ms. Castillo and Mr. Chamorro, who have been together for six years, have set a wedding date for Dec. 14 in Ms. Castillo’s home country of Nicaragua.

“I wanted it to be the 13, but that’s a Friday,” Ms. Castillo said, referencing Taylor Swift’s 𝐛𝐢𝐫𝐭𝐡day.