A Puppet (human, animal, alien, etc.) Or a stuffed toy that is used to masturbate into or onto. Male or Female although most won't admit it at some point they probably had a Stuff Puppet.
The last time I used my stuff puppet I had to peel it off the floor.
Puppet Stuff is a book on the site Quotev.com that consists of art, memes, shitposts, etc.
"Hey, have you read Puppet Stuff yet?
"What the fuck are you talking about"