Trosips

Killer Dusk Bunnies.  That's what Trosips are.  Living balls of dirt, hair, cobwebs and little crumbly bits of detritus.

Trosips come from the Red Steel campaign-- a swashbuckling-themed coastal setting in the vein of Alexander Dumas fiction. Set on the world of Mystara, the classic world where all the original 1st edition D&D games were set (more on that in a future post).

Trosips live in man-made dwellings-- castles, manors, houses, inns-- especially in all the nooks and crannies where genuine, non-living dust bunnies accumulate.  They're attracted to body heat and will congregate around a sleeping being in great numbers.  Such great numbers, in fact, that thy often accidentally smoother the sleeper. Because of this, dwellings along the Savage Coast, where the Red Steel game is set, are kept meticulously clean to discourage these critters.

 Trosips remain completely motionless when active, waking beings are around.  In this state they are completely indistinguishable from normal dust.

 According to the fluff text, assassins will sometimes use trosips to kill victims without leaving any traces.

I love these little oddballs so freaking much, you guys! You don't even know.  There's something so charming about a living dust bunny.  A KILLER living dust bunny, even!  If I ever have a chance to play a mage, I'd want a trosip as my familiar.  Heck, I'd just want a spell that would allow me to summon a herd of them.  Not to kill anyone, but just to have them scooting all around me like little dusty inchworms.

As to what they actually are-- I like to think they're colonial animals.  The ball of hair and dirt is just a shell for a mass of microscopic critters, maybe dust mites or tardigrades.  Or maybe just a single large amoebae-like organism similar to a deep-sea xenophyophore.