Not THE Willie Nelson, as he has personally clarified, Willie Nelson is a spiderlike creature, somewhat resembling an onion. He has taken up residence in the Aqua Teens' attic, although he is seldom seen. Nelson is a placid individual and is generally (though not always) courteous to others, which belies his grisly tendency to murder human beings and use them for food.
In The Shaving, Willie comes down from the attic on Halloween, asking Frylock if any mail had come for him (Frylock says that mail for a Willie Nelson arrived on occasion, but not knowing of Nelson's presence he at first forwarded it back and later took to simply throwing it out). He claims to have been driven to the house by an acquaintance for "doing 30 in a 25." Master Shake finds him to be the "gayest monster since gay came to Gaytown" and endeavors to turn him into a genuinely frightening one, giving him electric chainsaws and the pseudonym "Bloodfeast Island Man," in an ultimately unsuccessful attempt to scare Carl. Frylock does manage to find some mail for Nelson at takes it to the attic (followed by Shake), but is surprised to find various bodies, organs, and blood strewn about and therefore discovers Nelson's homicidal tendencies. Meatwad and Carl appear, having waited for them in an attempt to scare them; Willie nonchantly attacks Carl, exclaiming "Juice!" and ripping off his arms, then drinking his blood. Willie asks the Aqua Teens if they would also like some "juice", but they quickly go back to the main floor and board up the attic, leaving Willie and Carl inside.
In Party All the Time, the aliens in Frylock's dream have Willie's body.
In Robots Everywhere, Willie's bloody attic door is seen when Carl is trying to sell the Aqua Teens' former house to potential buyers. When the buyers ask about it, Carl tells them to ignore it.
In Aqua Teen Hunger Force Colon Movie Film for Theaters, when the Aqua Teens' roof is destroyed by the Insanoflex, Willie can be seen coming out of the destroyed roof.
In Eggball, Willie appears on Shake's pinball machine.
In One Hundred, he appears as a stylized version of himself, along with other monsters from the series, to chase the Aqua Teens.
The real Willie Nelson guest starred in "Baffler Meal," the episode of Space Ghost: Coast to Coast where the Aqua Teens made their first appearance. This is believed to be the reason behind the character's name.
In The Last One Forever and Ever (For Real This Time) (We Fucking Mean It), Willie appears during the end credits, still living inside the Aqua Teens' house years after the deaths of Shake and Frylock, though it has since been refurbished.
- The Shaving
- Party All the Time
- Robots Everywhere (referenced)
- Eggball (cameo)
- One Hundred
- Aqua Something You Know Whatever Theme Song (cameo)
- Aqua Teen Hunger Force Colon Movie Film for Theaters (cameo)
- Aqua Teen Hunger Force Forever End Theme (cameo)
- The Last One Forever and Ever (For Real This Time) (We Fucking Mean It) (Cameo)
- Willie drinks blood and calls it "Juice!"; this is ironic considering the entire premise of the first episode he was featured in was about making him a scary monster.
- Willie is the final character to have an on-screen appearance in the series.