Calvin Harris and Taylor Swift are definitely getting serious as the "Summer" singer reportedly spent the night on the apartment of the "Blank Space" hitmaker.

"The two musicians were spotted leaving Taylor's New York City apartment separately on Wednesday, after Calvin had stayed over following their romantic date night the previous evening," said Daily Mail. "The 25-year-old looked extremely cheerful as she stepped outside in a skimpy white romper, leaving her very long and slender legs on show."

This wasn't the first time that the British tabloid reported of Calvin Harris spending the night at Taylor Swift's apartment.

Last month, Daily Mail also published a photo of the EDM DJ leaving her New York Apartment on his SUV.

"Clearly getting close, the pair seemed comfortable with such public displays of affection," said Daily Mail. "Yet, the next day, Calvin cut a lone figure as he was seen driving his car back to his own Los Angeles property."

"Together, the pictures confirm nothing - but they will certainly get fans talking," it added.

The report came on the heels of the rumor that Calvin Harris cheated on Taylor Swift with a mystery brunette.

According to the tabloid Star, as relayed by OK! magazine, Taylor Swift reportedly confronted Calvin Harris when she saw the photos of her boyfriend leaving a Las Vegas event on May 16 with the woman.

"Calvin is acting like it's no big deal, and Taylor believes him. She's in denial about how serious he's taking their relationship," the source claimed.

The source added, "All Taylor's friends warned her that Calvin is a player, but she wouldn't listen to them. He's the biggest Dj in the world and spends his time in clubs surrounded by ladies. What's going to stop him from cheating?"

But with the photograph of Calvin Harris leaving Taylor Swift's apartment, however, it's clear that the lovebirds are still very much stronger.