If it exists, there is port of it.
That is the text of the rule. However, the exact opposite is true, as the rule refers to made-up characters who do not exist. Almost NOTHING that ACTUALLY EXISTS has porn of it, besides random whores putting themselves on the internet (and many thanks to them for trying to make rule 34 true). But really, rule 34 refers to drawn porn.
It should be re-written to
If someone imagined it, there is porn of it.