The singer is now engaged to actor Zoë Kravitz, 37, while Swift married NFL star Kelce at Madison Square Garden after a ceremony officiated by Adam Sandler.
Kravitz, a long-time friend of Swift’s, attended the wedding, while Styles remained in London due to his tour commitments.
Reacting on X, one fan said: “Harry Styles just sang Two Ghosts on Taylor Swift’s wedding day. What is happening!”
Another posted: “Singing Two Ghosts during her wedding day is objectively funny. Harry Styles you MESSY B****.”
A third added: “[Taylor] invited him, he sang it to show he’s spiritually there with her.”
Another joked: “He wanted to be there to stop [Taylor’s] wedding.”
A further fan pointed out: “Taylor said he was that guy who might interrupt her wedding … not quite close.”
The lyrics to Two Ghosts have fuelled speculation since the song’s release in 2017, with Styles singing in the tune: “Same lips red, same eyes blue”, before later adding: “Sounds like something that I used to feel.”
The chorus continues: “We’re not who we used to be, we’re just two ghosts standing in the place of you and me.”
The song has frequently been linked by fans to Swift, while her own 2014 hit Style has long been widely believed to reference Styles.
Speaking about her song in 2014, Swift said: “It’s about those relationships that are never really done. You always kind of have that person, that one person who you feel might interrupt your wedding and be like, ‘Don’t do it cause we’re not over yet’.
“I think everybody has that one person who kind of floats in and out of their life, and the narrative is never truly over.”
Styles first found global fame as a member of One Direction before launching a hugely successful solo career with hits including Sign of the Times, As It Was and Watermelon Sugar.
Swift, meanwhile, has dominated recent headlines following the conclusion of her record-breaking Eras Tour and this week’s wedding to Kelce, one of the most talked-about celebrity events of the year.
The couple exchanged vows at Madison Square Garden wearing custom Christian Dior couture designed by Jonathan Anderson, with Swift accessorising her gown with Cartier jewellery and Christian Louboutin shoes.
– BANG Showbiz