3:30 PM PT -- Diddy's attorney Jonathan Davis tells TMZ ... "No matter how many lawsuits are filed it won't change the fact that Mr. Combs has never sexually assaulted or sex trafficked anyone. We live in a world where anyone can file a lawsuit for any reason and without any proof. Fortunately, a fair and impartial judicial process exists to find the truth and Mr. Combs is confident he will prevail against these and other baseless claims in court.”

Diddy hired a former porn star to have sex with people at some of his legendary parties, and threatened to blackball her and her model boyfriend if she didn't comply ... according to a new lawsuit she's filed.

Adria English, who says her porn stage name was Omunique, says she first met Diddy around 2004, when her BF was auditioning for a Sean John modeling gig. In the docs, obtained by TMZ, Adria claims things got freaky with Diddy right out of the gate.

Adria claims her boyfriend and another model were asked to perform oral sex on Diddy in order to get the job. She says her BF refused, but he got a second chance when another Diddy associate offered him the job ... as long as he got Adria to work as a "go-go dancer" at Diddy's upcoming white party in the Hamptons.

She and the boyfriend agreed, and she indeed worked the party over Labor Day weekend 2004 -- the lawsuit includes pics of her there -- and says she subsequently worked other Diddy parties where she regularly had to drink alcohol laced with narcotics like ecstasy, and was encouraged to flirt with guests.

Although she did not have sex with guests initially, she claims Diddy "groomed" her into sex trafficking over time. Adria claims things ratcheted up when Diddy demanded she have sex with Jacob Arabov -- famously known as "Jacob the Jeweler" in hip hop.

According to the suit, filed by attorneys Ariel Mitchell-Kidd, Esq. and Steven Metcalf, Esq., she had "forced sexual intercourse" with him, and then was paid an additional $1,000 on top of what she usually got for working Diddy's parties.

She took a photo with Jacob after the alleged assault, while still at the party ... and claims Diddy himself personally congratulated her for having sex with Jacob, as directed, and told her job well done. Jacob is listed as a defendant in the suit.

Adria claims things got worse after that, because she was being "passed off" to other people at Diddy's parties ... and they, too, sexually assaulted her. She's also suing a woman named Tamiko Thomas, who she accuses of facilitating Diddy's sex trafficking operation.

In fact, Adria says Tamiko is the Ghislaine Maxwell to Diddy's Jeffrey Epstein.

She also claims Diddy promised to advance her career -- even helping her join a girl group to enter the music business -- but backed it up with forceful demands and threats to blackball her and her BF from the industry if they didn't comply.

She says she eventually did escape and returned to CA in 2009 and believes Diddy blackballed her and her BF as punishment.

We've reached out to reps for Diddy and Jacob the Jeweler ... no word back, yet.

Adria claimed she has suffered emotional trauma, including intimacy issues and painful memories, as a result of the alleged sex trafficking.

She's suing Diddy, Bad Boy, Tamiko Thomas, "Jacob the Jeweler" and others and seeking unspecified damages.