Glyceraldehyde Goofball

So, I think I worked this out. It's mentioned in a scene in PLL (Pretty Little Liars) S3E16, and means that Toby is Spencer's sweet drug that makes her delusional, because Glyceraldehyde is a sweet aldose, and a Goofball is a slang term for a Barbiturate.
(See also Goofball)

"You're my Glyceraldehyde Goofball"
"Erm. What?"
"My sweet sweet drug!"
"Right..."