The John Kricfalusi couch gag is the first couch gag of season 23
Homer makes Marge get him a beer, enjoying watching her get it in the process. During this, Bart places a "poopie cushion" under his father's backside. When Homer sits down, he makes a farting sound, causing him to get angry and strangle his son, resulting in his peanut-sized brain to pop out and fall in his beer. The scene ends with Homer pouring the drink in to the hole in his head.