All At Once by Leda Starr

Coral Valdez, a self-professed 'creature of pleasure', escapes from a small town to NYC, prostituting herself to men and women alike along the way. She falls for Tessa, a madame for lesbian hookers, and works for her once she gets to the city. Coral meets Bunny in a bar, but doesn't take their relationship seriously, and uses Bunny as an outlet for her personal degradations-until Bunny kills her in a fit of jealousy, just before Coral can marry this old man she met 'on the job'.