Gabriel 'Gabe' Dimas is Claire Fisher's boyfriend during their senior year of high school. She dated him but then broke off their relationship when he told the whole school that he had sucked her toes, leading to her getting revenge by putting a severed foot in his school locker. She did not speak to him until the death of his younger brother Anthony. His stepfather attacked him at his brother's funeral since he blamed Gabe for being in possession of the gun that Anthony got hold of, leading to his death.
Gabe ends up overdosing and Claire tries to help him recover. However, he holds up a convenience store, stealing the Fishers' embalming fluid to use for extra-potent joints, and pulling a gun on another driver while Claire is trying to drive him to a secluded area. They split up again and she later receives closure from a fantasy sequence in which she believes he has killed himself in order to be with his younger brother.