Rachel Cohen

Rachel Cohen is Lisa Simpson's imaginary friend. She is Jewish.

History
Lisa made Rachel to try to avoid other people and be with someone with the IQ as high as herself.

Rachel Cohen is element Rc on Lisa's Table of Geeky Delights.

Non-canon
When Lisa was young, she made Rachel up, as she had no friends. Lisa and Rachel often had tea parties together. Rachel got married in an imaginary wedding to a unicorn and Lisa attended the wedding. Eventually, Lisa outgrew Rachel and, with the advice from Marge, forgot about her.

A few years later, Lisa was playing with Janey when a lawnmower turned on and killed her. At the funeral, Sherri and Terri told Lisa they wanted to be her best friends, and then they died. Lisa went to a grief counselor and she ended up dead too. This all turned out to be Rachel, who was jealous that Lisa had new best friends and was killing them.

Lisa started to return to normal after, going back to school. Rachel then threatened to kill Milhouse. Lisa tried to get Rachel to stop, but she refused. Since Lisa was the only one attached to all the murders, she was arrested and put in jail, where she revealed to Rachel that Marge is the reason she forgot about Rachel and moved on. Rachel got angry at this and went to kill Marge.

When she arrives at the Simpson house, she tries to throw a knife at Marge, but Snowball V blocks it, getting killed in the process. She then tries to kill Marge using an iron, before Lisa and Bart, who helped Lisa break out of jail, stopped her. Rachel says that nobody will believe Lisa as nobody can see Rachel, until Homer comes along and says he can see her as he's drunk. Rachel attacks Homer, causing Homer to summon his imaginary friend, Sergeant Sausage.

Sergeant Sausage and Rachel fight for a bit before Rachel shoves him in a microwave and causes him to explode. When Rachel is getting ready to kill everyone, Lisa stops her by imagining her as an older woman, and then married to someone, causing Rachel to be defeated.

Behind the Laughter
Rachel Cohen may have been named after David S. Cohen, now David X. Cohen. Alternatively, she may have been named after Joel H. Cohen. Also, may have been named after activist and politician