Softpeter is the disgusting green drink you get in jail. If one has ever been in jail and was forced to drink it knows that it certainly lives up to its name. It makes it nearly impossible to achieve an erection, in hopes of decreasing the odds of masturbation/jail sex. Nobody knows for sure the contents of such and upon ingestion one wonders what, exactly, this mystery fluid is.
Person1 Man, i just spent 11 days in jail and all i could drink was water and this green juice, well, not actually juice but more like drink, a green drink.

Person2 Dude, that was softpeter didn't you notice you didn't have a boner the whole time you were in there

Person1 Well now that you mention it i didn't, as a matter of fact, i had a negative boner
by joethejabberwock July 17, 2009
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