The well-known music mogul faces accusations of exploiting his influence to force women, Cassie included, into abusive sexual situations, resorting to violence when they did not comply.

He has pleaded not guilty. Cassie sued Combs in 2023 alleging years of rape and abuse.

The suit was settled within hours, but was followed by dozens of similar legal claims and touched off a criminal investigation.

Here’s what you need to know about the 38-year-old star witness.

Cassie, a multi-talented singer, actress, dancer, and model, pursued her career aspirations from a young age by joining the prestigious talent and modeling agency, Wilhelmina.

Her music career launched shortly thereafter, when she left her home state of Connecticut for New York, where she signed with manager Tony Mottola and first met Combs.

Cassie is perhaps best known for the 2006 hit single Me & U, which secured the number one spot on the Billboard Hot RnB/Hip-Hop songs chart and number three on the Billboard Hot 100 all genres chart.

It was certified platinum by the Recording Industry Association of America.

The song was the lead single of her only studio album, released by Combs’ Bad Boy Records, and was self-titled.

She left the label in 2019.

As an actor, she appeared in several television and film projects including Fox’s Empire, The Perfect Match and Spenser Confidential. She made her acting debut in 2008 in Step Up 2: The Streets and contributed the song Is It You to its soundtrack.

She appeared in a number of music videos as well, including Wiz Khalifa’s Roll Up and Mario’s Just A Friend 2002.

Although she never released her long-teased sophomore album, at one point tentatively titled Electro Love, she did drop a few tracks: the RnB-pop Official Girl with Lil Wayne, Must Be Love with Combs, and Let’s Get Crazy with Akon.

And in 2012, Nicki Minaj tapped her for a feature on The Boys from Minaj’s Pink Friday: Roman Reloaded – The Re-Up.

Cassie is also a wife and a mother.

She married personal trainer Alex Fine in September 2019.

Their first daughter, Frankie Stone Fine, was born that same year and they welcomed their second daughter, Sunny Cinco Fine, in 2021.

Cassie met Combs in 2005 when she was 19 and he was 37. He signed her to his Bad Boy Records label and, within a few years, they started dating.

In her 2023 civil lawsuit, Cassie alleges Combs trapped her in a “cycle of abuse, violence, and sex trafficking” for more than a decade, including raping her and forcing her to engage in sex acts with male sex workers. Combs settled the lawsuit the next day.

The video closely mirrored an assault described in her lawsuit, which said Combs had already punched her that night, and she was trying to leave the InterContinental Hotel in Los Angeles when he woke and came after her.

In the footage, a man who appears to be Diddy, wearing only a towel, punches Cassie, kicks her, and throws her on to the floor.

The lawsuit alleges Combs paid US$50,000 ($77,268.41) to bury the video at the time.

Later, Combs apologised for the assault on Cassie in his first real acknowledgment of wrongdoing since the stream of allegations began.

Among other things, Cassie alleges Combs raped her when she tried to leave him and often punched, kicked and beat her, causing injuries including bruises, burst lips, black eyes and bleeding.

She also alleges that Combs was involved in blowing up rival rapper Kid Cudi’s car when he learned that Cudi was romantically interested in her, and she alleges that Combs ran out of his home with guns when he learned that Suge Knight, a rival producer, was eating at a nearby diner.

On the first day of Combs’ sex trafficking trial, a witness, Daniel Phillip, said he was a professional stripper who was paid US$700 to US$6000 ($1081.76 to $9272.21) to have sex with Cassie while Combs watched and gave instructions, with the first encounter in 2012.

Phillip told jurors that he stopped meeting with the couple after he saw Combs throw a bottle at her and then drag her by her hair into a bedroom as she screamed.