Willy Weasel

Willy Weasel (possessed by Jerry Robert Wills), is the titular main antagonist of the 2021 horror thriller film Willy's Wonderland.

He is an animatronic weasel and a mascot of Willy's Wonderland. Seemingly a friendly animatronic, Willy is possessed by the soul of Jerry Willis, the original owner of the restaurant and a notorious serial killer who formed a team of Satanists and other serial killers to help him murder unsuspecting families at the establishment. To avoid being arrested, he and his team performed a Satanic suicide ritual to transfer their souls into the animatronics, possessing them and actively killing and devouring everyone in their sight.

Origins
In 1996, Willy Weasel was once a friendly animatronic along with the others. However, Jerry Willis, the original owner of Willy's Wonderland, and his team of serial killers wore some character costumes to kill some children and their families in a party room. One time, Jerry put on the Willy costume and stalks behind the birthday boy with his family before proceeding to kill the child. When the boy was killed, Jerry kidnapped the boy's sister and murdered her as well, causing everyone to panic. Later at night, Jerry and his friends killed themselves in a Satanic ritual before the authorities arrived, preventing from being captured. After that, Jerry's soul was transferred into Willy Weasel, while his crew get into the other animatronics.

Ten years later, Willy's Wonderland was reopened by the new owner, Tex Macadoo, to keep the people unaware of this horrific past. Suddenly, Willy and the other animatronics (possessed by serial killers) have man-eating behaviors to attack, scare, and even kill children, as seen when Willy attacks and eats a portion of a boy's chest off his body. After the children were found either dead, trauamatized, or serioulsy injured, Willy's had to be permanently shutdown once again.

Tex tried to have the place torn down, but Willy killed the contractor and his family and no one took the job of tearing it down so they decided to leave it as is, locking it up and letting the place rot. Unfortunately, it didn't stop Willy from killing other residents in their own homes and in other places (an ice cream shop, a hardware store, and even a school, to name a few) so the town reluctantly decided find people and trap them to be killed in exchange for leaving Hayesville alone.

Willy's Wonderland
In the present, the quiet protagonist is hired to be the janitor at the old abandoned Willy's Wonderland to clean everything for the rest of the night so his car's wheels will be fixed by the next morning.

Later at midnight, Willy remains in the show stage throughout most of the film while his gang moves out to kill the Janitor and Liv's friends, but the Janitor kills them all after the animatronics killed all of Liv's friends, except for Liv herself. When the Janitor confronts Eloise Lund, Willy gets out of the show stage and kills Eloise from behind after being called out to kill the Janitor, but her instead. Willy brutally slashes around the Janitor who's been stunned by the weasel's attacks into the chest and throws him into the ball pit. Thinking he's dead, Willy walks away, but the Janitor survived and uses his weapons, two mop sticks and a bag of his sodas.

Willy confronts the Janitor into a real final battle, and the two engage into a brutal combat. The Janitor gains the upper hand and eventually defeats Willy by pummeling into his head multiple times on a bloody rage, mortally wounding Willy. For a fatal blow, the Janitor finishes off Willy by tearing his head off, killing Willy.

With Willy destroyed, Jerry's soul is now sent to Hell as punishment for his crimes, and the Janitor avenged all deaths of innocent lives, including the children and the townspeople Jerry had murdered, as well as Liv's friends killed by the animatronics who were defeated by the Janitor himself.

Trivia

 * Willy was the sixth animatronic to become active and get killed by the Janitor in the film.
 * He’s based on Freddy Fazbear as an animatronic, although as a human he is most likely based on William Afton.
 * In contrast to the animatronics from Five Nights at Freddy's, who were possessed by Afton's victims and began killing due to misguidedness from being unable to recognize their killer, Willy and his gang were possessed by serial killers who were evil from the start and continued their murder spree out of their own free will.