The Sniggles are fucking weird, on the surface they seem to be a version of the Smurfs, you've got Smurfette and Snigglette, Papa Smurf and Papa Sniggle, it's pretty clear. But I don't know shit about the Smurfs other than what's in the live action films with Count Olaf (Neil Patrick Harris) but the two songs in Watcher World tell a surprising amount about the Sniggles.
In the Blinky Song, the Sniggles describe Blinky as their "boss", implying that they are employed and possibly have a capitalistic society, in Drowsy Town. However as Blinky seemingly controls the Sniggles basic needs, "our boss gets mad, and then we don't eat for a week", which conveys a servant/master dynamic, so they might not be getting paid in a form of currency, just the fact they are able to eat and survive is payment enough.
The fact that there is a "Sniggle mold", as described by Snigglette in Drowsy Town, Watcher World, means the Sniggle community has stereotypes about how they should act and what they should be, presumably set in place by the Lords in Black to keep them complicit. The Sniggles are being oppressed, and some are seemingly aware of that fact as Snigglette wishes to "change my Sniggle frown, I'll break the Sniggle mold, I'll trade these wings for gold". The use of the noun "gold" does imply that there is a form of currency or value of certain items like gold, which further cements the capitalist society storyline, or potentially even a dictatorship, where only the immensely rich and powerful can change anything, where the Lords in Black are the dictators. But it's only a dream to Snigglette, something she knows she cannot truly achieve, resigning herself to stay in her place and not leave Drowsy Town to chase her dreams of making a difference in the world, as others around her shame her and threaten her with making Blinky mad, potentially condemning her to death.
There are also different types of Sniggles, depending who they work for, Wiggly Sniggles appeared in Black Friday, Blinky's appeared in Watcher World and Nibbly's in Honey queen. They all seem to share a similar look, with some antenna, which in Black Friday only appeared on presumably 'female' Sniggles (the actors that portrayed these Sniggles are fem presenting), but that thought has been challenged by the Sniggles in The Nibbly Ditty, as they are played by Curt Mega and James Tolbert and both are wearing antenna. Antenna does not dictate sex, and they may even have the same anatomy. But they are definitely able to reproduce, seemingly sexually as Snigglette wants to find a "handsome Snoog and snort his handsome hooves", then they'll have "two Snoozles", as two parties are seemingly needed, whether or not they have defined genders at all. The t-shirts defining who the Sniggles work for are the only thing that sets them apart, it seems.
They all also have wings, and possibly no hands, as wings take their place. But these wings may not be used for flying, and are closer to hands/claws as they are able use a hammer to hit things, as seen in Watcher World.
Going off this physical information, Sniggles have antennas, wings that act as arms, hooves and the ability to wear t-shirts.
I hope all your Sniggle OCs fit this criteria. /j
