Spill the beans on what? The chair?

I'm pretty sure it ended up in some guy's house and ... Resulted in quite a few deaths. And, quite possibly, someone sitting on the chair and going insane.

Hell, on a re-read I wouldn't discount the very idea that the being OP saw is actually the dude who found the dimensionally-fucked chair. This guy found half a chair, and everyone who touched it was eviscerated in almost exactly the way OP here says would happen. That guy figured out a way to get onto the chair without exploding across multiple dimensions, then mentioned that he thinks more people need to see this shit before disappearing.