Place it right after the drink is shown, then follow it with a fart sound for a second beat before cutting to the reaction. A vine boom can close the moment once the joke has landed, keeping the edit focused on the drink gag.
このサウンドについて
This is a short gross-out meme clip built around the phrase carbonated poop water, lasting just under ten seconds. It lands with a mix of disgust and laughter, the kind of deliberately revolting joke that makes listeners groan before they laugh. Its humour comes from the absurd drink description itself, not from a scare or a punchline twist.