Orgasmic Execution

An executioner got the unfortunate (or maybe fortunate?) task of executing his own girlfriend. He tied his girlfriend's hands above her head and then prepared to slit her throat. However, his girlfriend doesn't want a quick death and preferred it to be as excruciating as possible. He stabbed her in the navel but she seemed to enjoy it. She asked him to torture her even more so he pulled her guts out. She still wasn't satisfied.

What did the executioner do to make his girlfriend experience an orgasmic death?