Rocko's Modern Life/Fridge

Fridge Brilliance

 * In Future Schlock, Heffer and Rocko don't seem to have aged much or to be otherwise worse for the wear after seventeen years in space. If they traveled at relativistic speeds, more time would have passed on Earth than would have on the spacecraft.
 * Ed Bighead, a cane toad, has an adversarial relationship with Rocko, who's from Australia.
 * In Feisty Geist, Mortimer Khan takes over Filbert's body. Just as Rocko and Heffer prepare to squirt him with Spirit Away (TM) cream, he is already spirit free. They find him just washing his hands by the sink after using the bathroom. Mortimer surprise attacks Heffer as a toilet soon after. Mortimer didn't willingly leave Filbert's body, but passed out of him while he was on the can.

Fridge Horror

 * Whenever Heffer is called a cow, he or his dad will insist that he's a steer. A steer is a castrated male bovine.
 * More Fridge Brilliance, Heffer comes across as gay. He's able to talk to girls that make Rocko blush, and gets jealous if Rocko finds friends besides him. In a world where people are animals, him being neutered, this makes perfect sense.