Hunt the Killer — Day Keene

He was an ex-con walking the last steps toward freedom. He was an ex-con torn between the lust to get the man who “sent him up the river” and the vow to go straight; torn between returning to his faithful wife and his pulse-quickening Cuban mistress...
As the prison gates closed behind him het met -- not his wife, but the enticing Cuban. She took him to a private retreat in the woods. She was everything that he remembered.

Then suddenly she was cold -- cold and dead in his arms!