The crimes Omar Cash is accused of are horrific enough: carjacking a couple outside a Philadelphia club, murdering the driver in Bucks County, and raping the man's girlfriend three times.

Adding to the trauma was Cash's exultant behavior between the attacks - laughing, singing, and swaying to the music on the car radio, his alleged rape victim testified Friday in Bucks County Court.

"He sang to the music. He moved to the music. He was really happy," the woman, sobbing and gasping, said of the minutes after the execution-style shooting death of her boyfriend, Edgar Rosas-Gutierrez. "I don't think this is a human being."

Prosecutors are seeking the death penalty for Cash, 28, of Philadelphia, in the May 11, 2008, slaying. The body of Rosas-Gutierrez, 32, was found on an embankment at Street Road and Route 1 in Bensalem, a bullet through the back of his head.

Cash is also accused of kidnapping and raping the Brazilian-born woman, whose translated testimony consumed most of the trial's fourth day. The Inquirer is withholding her identity because of the nature of the crime.

Cash awaits a second murder trial in Philadelphia, where he is charged with shooting to death a 19-year-old man at a car wash a few weeks before the slaying of Rosas-Gutierrez.

Despite a lengthy list of arrests on charges of attempted murder, rape, robbery, drug-trafficking, theft, and firearms violations, Cash has spent less than two years in prison. According to an Inquirer series last year on dysfunction in Philadelphia's criminal justice system, Cash's history exemplifies the problems of witness no-shows and procedural bungling that have long beset the city courts.

Jurors in the Bucks County case have not been told of that history. Nor, because of rape-shield laws, were they informed that the woman, 43, had admitted to working as a call girl after coming illegally to the United States a year before the slayings.

Her night of terror, she said, began as a special occasion. Rosas-Gutierrez, saying he planned to marry her, had arranged to introduce her to relatives that night at Jalapeño Joe's, a club on Castor Avenue in the Crescentville section.

The couple returned to their car around 3 a.m. in a dark, deserted section of the parking lot behind the club.

"Edgar embraced me, hugged me and kissed me, and told me he loved me a lot," the woman testified. Then Cash jumped into the back of the car, pointed a handgun, and told Rosas-Gutierrez to drive.

Alternating between laughter and harsh shouting, Cash demanded the couple's money, then ordered the woman into the backseat, she said. There, he forced her to have sex, she said.

"He would talk and laugh," the woman testified, adding that she could not understand most of what Cash said. "I didn't even have the courage to put my clothes back on."

About 4:30 a.m., the car stopped on the Street Road exit ramp. Cash got out and forced Rosas-Gutierrez from the car, she said.

She thought of fleeing, but "I had no strength," she said.

A gunshot sounded, and Cash returned, his left hand and clothing bloodied.

"He left very fast," he said. "I said, 'I have to get Edgar.' He was was laughing."

Cash then pulled into a parking lot, pushed her onto the car hood and raped her again, the woman said. She ran to the vestibule of an apartment building, but he caught her, she said.

Cash drove on and ultimately checked into a motel in Lawrence, N.J., where he raped the woman a third time, she said. She finally escaped by fleeing in a hallway and scrambling over the check-in counter, where a startled clerk called 911.

"He thought I was crazy, because I just kept saying, 'Help! Help!,' " she testified.

Cash was later arrested in New York City, police said.

Under cross-examination, the woman said she had come to the United States illegally in hopes of helping her children and grandchildren in Brazil. She said she since had legalized her status here.

Contact staff writer Larry King at 215-345-0446 or lking@phillynews.com.