The Human Cymothoa Exigua

Never pause mid-sentence when dealing with Backchat Barry. He can't resist, he won't resist. He'll finish that sentence for you before you've drawn breath, and fire off three responses while you're still dazed at the rudeness of the whole thing and just how wrong he can be. He has whole conversations by himself, staring at the non-participant, talking for him, then, with a "Glad we could sort this out, thanks," he's gone. He doesn't even know it's wrong.

"Barry, have you seen those ah.."
"Spreadsheets you were looking for? No I think they're still on a cd somewhere. I'll go have a look around - talk to you soon, bye!"
"... bits of parsley in your teeth, I was going to say... bye..."

"Hi Dorothy."
"Barry, what can we..."
"Do about the inaccurate reports? Three options - hide them, use them as is, or fix them. Fixing them's no good, we already ran them wrong once who's to say they wouldn't still be wrong. Hide them's no good, we put in a lot of work, don't want to waste the resources do we? So we'll use them as is and hope noone notices. They never do. Right. I'll go send them out now. Good thinking!"
"...have for our office morning tea? Oh, right... bye. I guess I'll get a couple of cakes."

You should see him trying to deal with the petty cash gnome. It's a subconscious battle of wits, Barry waiting for a hint of a thought to emerge from the gnome's domelike, while the gnome voicelessly searches every possibilty of escape or sleep, methodically crossing off ideas one at a time.

Backchat Barry, you see, is a human cymothoa exigua. He will kill your tongue, then become your tongue. And that's just gross, especially if you've ever seen Barry.