I think it's all one thing. I know there's also balloons that you can fit in (minus your head) and inflate them, but I'm not sure if that's also part of it or not. I feel like somewhere on the internet I've seen one of them being used in an erotic manner at some point.

I just know balloons are a thing, I think I remember popping being part of it but now that you say it idk.

women popping clown balloons by doing kegels

surely exists, but shan't be searching for confirmation