Like the other members of the Bowers Gang, Belch is a rough and aggressive bully who takes pleasure in tormenting Bill and his friends.
However, he is often times disgusted and horrified by Henry’s sadistic nature; a couple of examples are when Henry torturously cuts Ben’s stomach and when Henry forces him to use a cat for target practice.
As school lets out for summer, Bill, Richie, Stan, and Eddie walk right past Belch, Patrick, Henry, and Vic, all four of them just stand there, looking at them with malicious intent. They torture them outside shortly afterwards, with Belch burping in Eddie's face. Later on, as Mike Hanlon, who has come into town to deliver some meat, hides from them in an alley, they attempt to run him over; Henry harshly tells Mike to stay away from Derry, and Belch gives him the finger.
While leaving the library, Ben Hanscom, whom most people call "The New Kid", is ambushed and captured by Henry and his cronies. Belch initially takes pleasure in harassing Ben, but is sickened with horror when Henry goes so far as to carve an "H" on Ben's stomach with a knife. Ben manages to escape by pushing himself over the side of the bridge, then tumbling down a hill, and fleeing to the Barrens, where he is rescued by Bill and his friends. Henry and his henchmen chase after him, with Henry losing his knife while rolling down the hill; while Henry and Vic search for the knife, Belch and Patrick split up and continue the chase, leading to Patrick getting killed by a demonic clown after going into the sewers, thinking Ben was hiding in there.
A couple days later, Henry, Belch, and Vic are torturing Mike at the standpipe. Fortunately, Beverly, Bill, Ben, Eddie, Stan, and Richie turn up to save him, and the seven of them engage their rivals in a rock fight, with Belch and Vic eventually fleeing.
In August, Belch, Henry, and Vic are using a pistol for target practice. After shattering a couple bottles, Henry tells a reluctant Belch to use a cat as the next target. Before Henry has a chance to pull the trigger, his father arrives and reprimands him. While Belch and Vic stand by Belch’s Trans-Am, a furious, humiliated, and vengeful Henry sits in front of the car. After killing his father, Henry kills Belch and Vic, then steals the car.
It: Chapter Two
Belch appears briefly alongside Henry and Vic in a flashback Richie has when he plays against Henry’s cousin in an arcade.
Differences from the source material
He seems to be the closest to Henry as even though he was reluctant to let Henry shoot a cat and cut Ben, he still always listens to Henry and seems upset when his dad shoots a gun at him. He is also seen patting Henry on the back after they bully the Losers.
Although they don't interact much Belch seems to be the only one to care for Patrick as shown when he mentions about Patrick's dad having no new information about Patrick in a deleted scene.