Boston (CNN) -- A juror wept Friday as James "Whitey" Bulger's former partner told a tragic tale of a slip of the lip and the ensuing result -- the strangling death of a 26-year-old woman, who was killed because she'd heard too much. What made this recitation of deadly details different from the ones that preceded it during reputed mob boss Bulger's trial in federal court was that the victim had been the girlfriend of the witness. "It's affected me and it's going to affect me until the day I die," Stephen "The Rifleman" Flemmi said in the first humanizing testimony the jury had heard in two days of recollections about multiple murders and extortions.
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Debra Davis was the girlfriend of "Whitey" Bulger's partner, Stephen "The Rifleman" Flemmi
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Flemmi testifies Bulger strangled 26-year-old Davis in 1981 because of what she knew
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She died after Flemmi told her about his and Bulger's link with a rogue FBI agent
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Flemmi: "I couldn't do it...(Bulger) knew it ... he said, 'I'll take care of it, I'll do it'"
Flemmi was Bulger's number-two front man for nearly two decades, when prosecutors say @placeholder reigned terror over Boston.
"He strangled her all the way down to the basement...when he got to the basement she was dead," Flemmi told the jury, referring to Bulger and @placeholder's girlfriend, Debra Davis.