If you can imagine usin' Magic's johnson without a condom
from Royce Da 5'9" (Ft. Bun B & Slaughterhouse) – Nobody Fucking With Us Lyrics on Rap Genius
Meaning
Johnson = Slang term for penis
Magic Johnson, the famous basketball player, also tested positive for HIV

If tested positive for HIV sexual intercourse without a condom would contract the virus to any other partner(s).
To help improve the meaning of these lyrics, visit "Nobody Fucking With Us" by Royce Da 5'9" (Ft. Bun B & Slaughterhouse) Lyrics and leave a comment on the lyrics box