Who is Jisbella McQueen from The Stars My Destination and what is their importance?

Jisbella McQueen is imrpisoned at the Gouffre Martel at the same time as Gully Foyle. She makes contact with him via the acoustics of the prison, and when he makes his escape, she goes with him. Her relationship with Foyle is built on both affection and revulsion. She takes Foyle to a surgeon, Henry Baker, to have his tattoo removed. Together, they travel to the wreckage of the Nomad to retrieve the treasure hidden aboard it. Jisbella is then abandoned by Foyle, but meets Dagenham, with whom she forms a deep attachment and bond.