A third woman was allegedly sexually assaulted by Davidson at the Cannes Film Festival in France, with more footage captured.
He is accused of filming a fourth woman committing a sex act on him without her consent and later raping her, before making her clean his home.
Mr Hearnden said: “She was being used as some sort of sexual slave. He wanted to have sexual intercourse five or six times a night. When she said it was too much, he forced her to have sex.”
The fifth victim is said to have woken to find Mr Davidson having sex with her.
Mr Davidson replaced Tony Hadley as Spandau Ballet’s singer in 2018, but when the band finished its tour in Europe, he claimed he was “ignored” by management.
A day after Mr Davidson told the band he was leaving, other members of Spandau Ballet appeared on national TV announcing they would not perform again unless Mr Hadley rejoined.
Speaking about his departure 11 months after joining the band, Davidson previously told The Sun: “I told Spandau I wanted to leave and they wished me luck. I couldn’t afford to be left on a shelf, not knowing where my next meal was coming from.
“I never even got to say that I quit, to own any part of my story. I was so humiliated.”
Mr Davidson, of Finchley, north London, has claimed all the encounters were consensual. He denies three counts of rape, three counts of sexual assault, one count of voyeurism, one count of intimidation and one of controlling behaviour.
The trial continues.