OnlyFans announced Friday that it reached a deal to sell a roughly 16% stake to Architect Capital that values the porn streaming site at $3.15 billion, after the Silicon Valley investment firm struggled to clinch backers . Fenix International Limited, which owns OnlyFans, said the deal includes a $535 million investment that will help the revolutionary nudie site offer new financial services for its creators, “who are often underserved by traditional financial institutions and products.” Architect Capital is set to receive backing from a special-purpose vehicle with money raised from a group of investors. James Packer, a media and casino mogul who is one of the richest people in Australia, and Sam Lessin, a venture capitalist and early investor in Venmo, are among those backing the deal, according to the Financial Times . James Packer at a Crown Resorts general meeting in Melbourne, Australia, on Oct. 26, 2017. Getty Images OnlyFans declined to comment.…