We came up with this name by considering the following factors. First of all, Jeff are obsess with candies and a synonym for candy is "sweet". In addition, when we eat candy, we also can taste the sweetness in the candy. Interestingly, Jeff's childhood is a very dark and tragedy story which contrast with the adjective sweet. However, the word sweet when go with the word "dream" can mean that though Jeff is a psychopath, a serial killer, deep inside him still have a very desperate wanted for parents' love, a cozy, happy family, a "sweet" childhood.
On the other hand, you can also understood the title in a different way. "Sweet dream" is something you say to wish somebody have a good sleep, the same with "good night!". Related to sleep, we have the definition of a "eternal sleep" - once you sleep you would never wake up - which is similar to death. So the phrase "Sweet dream" could be what Jeff tell his victim before he kill them.
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