Live fast die young leave a good looking corpse

Often quoted by Christian Slater's character Clarence in True Romance.

Yes, it is used ironically by screenwriter Tarentino, for Clarence is not realizing the numbing power of love on would-be firebrands.

Clarence also often speaks with the ghost of Elvis, who did not leave behind a good-looking corpse.

The origin of this phrase (AFAIK) lies in the 1949 juvenile delinquent movie Knock on Any Door, starring Humphrey Bogart as Andrew Morton, the conscience-striken lawyer, and John Derek as Pretty Boy Romano, the young punk. As a thug in a street gang and eventually as a career criminal, Romano lived by the motto,

"I wanna live fast, die young, and leave a beautiful corpse!"

While representing Romano during his murder trial, Morton decides that given the terrible conditions in the slums, it was inevitable that Romano would turn to a life of crime. "Knock on any door," Morton argues to the jury, "and you'll find another potential Pretty Boy Romano."