AceShowbiz -

After hinting that her upcoming album "Witness" would have "no one thing that's calling out any one person," Katy Perry didn't seem to keep her words when she released "Swish Swish" and confirmed that it was a diss track aimed at her nemesis Taylor Swift. The "Dark Horse" hitmaker has now sparked rumors that she plans to release another diss track and takes Taylor's ex-boyfriend Calvin Harris along the ride.

Not stopping there, the pair are reportedly building a romantic relationship to get back at the "Shake It Off" singer. A source tells Radar Online, "At first Katy and Calvin were strictly professional. But then Katy brought up Taylor, and Calvin was more than happy to vent. He poured his heart out, and she goaded him on!"

The alleged source further claims that Calvin and Katy haven't stopped talking about "how annoying it is that Taylor is always made to be a victim. They both agreed that she's a total fake." Katy has always found the DJ "sexy" and that they "planned to strike when the timing was right."

"They genuinely have a lot in common. It's icing on the cake for Katy that she can drop this bomb on Taylor," the source adds. "There's only one goal for Katy now, and that's for a romance with Calvin to go public."

As previously reported, Katy and Calvin are "bonding" while making music. "Katy and Adam [Calvin's real name] really bonded while making their track, and have been in constant contact ever since," an insider claimed. "Besides their rivalry with Taylor, they've actually got lots in common-- they've read the same books, and love the same music. She thinks he's really handsome and talented. And he seems to be really nice."