[quote=@Sniblet]Less than fully confident that this is the place, because I [i]do[/i] adore that ROBLOX super-casual 10-second-post pacing, but it looks more worth a try than any of the Discord RP servers I've lurked in.[/quote]

If that is the content you're looking for, your best bet would be in the Free RP section rather than any of the others. I can't say anything in regards to exact speed (personally I doubt you'd get a reply back in mere seconds unless they happened to be on at the same time as you), but it is certainly the fastest place on the Guild as the content there is primarily dedicated to short, one-liner burst posts.