Hopeless romantic Taylor Swift has it bad for Harry Styles of One Direction. Almost bad enough to -- stop us if you've heard this before -- buy a house near him.

Us Weekly reports that Swift, 22, is completely smitten with Styles, 18. "They lit up when they saw each other," a source told the mag about their recent 'X Factor' excursion. "[Taylor] was a puppy dog. Harry picked her up and carried her to the trailer!"

This latest development echoes everything that Mario Lopez spilled, too. If this "puppy dog" stuff sounds familiar, the same thing reportedly happened with Jets quarterback Tim Tebow ... and that didn't end so well.

Now, rumors are swirling that Swift, who's looking to buy a home in London, is specifically doing so to be closer to Hazza. She's said to have her real estate agents looking for a place right around the corner from Harry's pimped-out $3 million mansion -- and that she's asking Harry for help finding a place. "She's even asked Harry if he'll come and look at some places with her, since he knows the area," a source said.

Of course, the last time Taylor bought a home near a guy, the relationship didn't end well, so she may want to consider a home a few blocks away to be safe ... especially if new rumors that Harry still has the hots for model Cara Delevingne are true!

Watch the Taylor Swift 'Begin Again' Video