Naw, they're really getting into character what with belting out Karaoke favourites with Ed Sheeran and the rest of One Direction, before stealing back to their NYC hotel at 4am in the morning.

After One Direction's Madison Square Garden gig on Monday, the 'couple' teamed up to sing a rendition of Kenny Rogers and Dolly Parton's classic Islands in the Stream at the Hudson Hotel.

A source told The Sun: 'It was brilliant. There was a huge cheer when they got up.'

Following the performance, Harry wrote on Twitter: "Last night was the best thing I have ever done. We're on an Island over the Stream..." Right so.

Taylor and Harry were then joined by Niall Horan, Zayn Malik, Louis Tomlinson and Liam Payne, and Ed Sheeran (why not) - to sing Backstreet Boys' 1998 hit I Want It That Way. Then Ed teamed up with the lads for a rendition of Vanilla Ice's Ice Ice Baby - probably because it was released the year most of them were born. 

Harry and Taylor - who went for a romantic/public stroll around New York's Central Park prior to the gig - also performed Sir Elton John and Kiki Dee's classic hit Don't Go Breaking My Heart before heading back to their hotel in the early hours.

One partygoer told the Daily Mirror: "It was the perfect song for a new couple - they were both giggling as they sang it to one another. It was very fun and very relaxed. Everybody was in really high spirits. You could tell they are very comfortable in each other's company. They were still smiling when they disappeared back to her hotel hand-in-hand in the early hours of the morning." And just to compound things for photographers, they both emerged a few hours later "within moments of each other", with Harry was clutching his toiletry bag.

Hang on a second. Is anyone else having difficulty believing that 18-year-old Harry Styles off One Direction knows classics by Dolly Parton and Elton John...? Yeah, I know the whole point of Karaoke is having the lyrics on screen, but what of the melody? The harmonies? The pizazz?! Just sayin'.

>Liam Payne and Leona Lewis are now back with their respective partners...