"Nancy Spungen was a model student, who became Sid Vicious" girlfriend. After meeting him, they both become addicted to chocolate (replacing drugs in the episode), which turned their lives out of control. When Sid destroyed one of the Sex Pistols shows, she made him quit the band and start a solo career, with her composing his songs. Nancy is portrayed by Lisa Simpson.
Behind the Laughter[]
In real life, she wasn't a model student. She was actually a rebellious teenager that ran away from home and moved to New York, where she met Sid. She was supposedly killed by Sid on October 12, 1978 with a stab wound to the abdomen.