A term that is used as a euphemism to describe someone who has contracted
HIV or AIDS.
The soup reference comes from the letters found in the alphabet that spell out the names of the variation of the disease (i.e. HIV the virus that causes AIDS).
see also; soup,
chicken noodle soup
Rob: Yo, I jus seen Carl the other day, and dude is mad skinny son.
Jay: Thas that
soup man.
Rob: Soup? *confused*
Jay: That alphabet soup.
Rob: Wha--oh daaaamn!
It's like that cuz?
Jay: Yup,
it's like that son. *nodding knowingly*