Diddy and Sienna Miller apparently aren't going to let the rapidly churning rumor mill get in the way of their good time. The pair, who have repeatedly pooh-poohed chatter that they're anything more than chums, reportedly rendezvoused Monday night in Ibiza.

The semi-famous starlet, whose look-at-me black pleather hot pants and gold, knee-high boots belied her shyness with paparazzi, turned up at the newly single mogul's soiree at hot spot DC-10.

The London Daily Mail reports Miller and Diddy later headed to her villa in order to "continue the partying."

This was the latest tête-à-tête for the twosome, who were first spied in each other's company back in January.

According to the Sunday Mirror, Diddy was now "expecting romance" and supposedly stocked his yacht with "candles and endless bottles of fine Cristal champagne on ice" ahead of Sienna's arrival.

Still, their self-proclaimed buddy status is getting a boost from an unlikely source.

In a candid interview that will likely prompt Diddy to have all future flames sign ironclad non-disclosure agreements, ex-girlfriend Kim Porter opens up to OK! about life with the meticulous multi-hyphenate, including dispelling rumors that his friendliness with Sienna contributed to their July bust-up.

"They're just friends," she assures the mag. "That wasn't the cause."

Porter, who is mother to Diddy's twin 7-month-old daughters and 9-year-old son, also discloses the inner workings of their 10-year "on-again, off-again relationship."

" ... [I]t came to a point where it was time for me to move on with my life. I had invested a lot of time in that relationship, and it wasn't going where it should have been going," she blabs. "So it was time to [end it]. In a relationship, it's important that the people are on the same page at the same time. And we weren't on the same page."

This wasn't the first time Diddy and Porter were on different pages. They previously parted ways in 1998, and he quickly took up with Jennifer Lopez, a headline-generating, handcuff-tinged romance Kim views as nothing more than a superficial dalliance.

"It was an embarrassment. I never thought it was real," she snipes. "I knew what was going on with him. Despite what you see in print and when the cameras are flashing, what's going on in someone's heart may be totally different. He was still [in love] with me. I never looked at their relationship [as serious]."

She also says that just because she and Diddy never tied the knot, that "didn't determine what my relationship meant with him," adding that marriage "really wasn't the top priority on the list."

Back in December, Diddy admitted to Essence magazine that while Porter "deserved to get married," he wasn't yet ready to settle down.

"It's that I'm just learning how to be a good boyfriend," he explained. "When I'm finished with this step, I'll move on to the next."

Porter, for her part, reveals to the magazine that she didn't have blinders on when it came to Diddy's extracurricular activities.

"I will never sit here and say that Puffy -- or any man -- is 100 percent faithful. I just don't believe it," a skeptical Kim asserts. "Some of you are, but I'm not going to sit here and say that I didn't believe that he cheated on me. I would never say that. I'm aware that he's cheated. Has it affected the trust value? Yes, of course."

Concludes Porter, "I have a history with him, and he's the father of my children. Just because I love him, that doesn't mean that we can be together. But I'll always have love for him."

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