Solidified jizz capsules from Ron Witkowski, an extremely rare resource, often used in the production of Ron Cookies see also, The Fortress of Ronitude
Loosely translated (with sincere apologies to Latin scholars everywhere), "people are assholes".
Often said with a resigned tone when something unpleasant has happened to you, and it's viewed as the inevitable consequence of declining politeness and consideration by others.
Roger: Dammit, look at how someone parked me in ... I can't get my car out of the space and I'll be late to meet Fred for lunch.
Tom: Well, Rog, you know what they say ... publicum rectumium