Okay, Clown anatomy, capital C, that's where it gets really weird. I mean I can give you the footnotes, sure, but Fuller didn't exactly run seminars on Clown biology. He didn't run seminars period, and frankly neither did Manny or the Ringmaster, but really once you get too esoteric you might as well be preaching to the shareholders.
No, I can't tell you who they are. Not just because it'd break Manny's heart, really, I have zero clue. He sends me bits and pieces every now and then, out of pity or contract or really, maybe the poor lug misses my dashing personality. Buuuuuut yeah, no clue who bankrolls it.
Back to Clowns.
Okay, you gotta understand: it's kinda rude to just walk up to Clown and ask "Hello, sir, madame, or otherwise, what do your insides look like?". Come to think of it, though, a few'd already seen my insides, so I probably stood a better chance. Still, hindsight is 2020, which if the marks on my wall are any indication, 's coming around in four years time. Oh yeah, happy belated anniversary, by the way, here's to ten more years living my best life as the cyclothymia eats me from the inside-out. Don't worry, little joke.
I can give you my best educated guess of course, but keep in mind my schooling stopped at eight. So, three kinds of Clowns exist: "born" Clowns, "bred" Clowns, and "turned" Clowns.
Most Clowns are born Clowns. How? I'm not entirely sure. You can see them coming in and out of the Ways, and they are freaky, Doc. Like a parody of a human. I mean this in the best way possible, of course, and when you think about it we are pretty funny as a species. I was not allowed to talk to the born Clowns.
Now, the turned Clowns…

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"Sharp as ever, Barney." In the seconds or so it took to land three bullseyes in a row, Saint's typical deathly silence had erased him from the little unseen world at the back of what Barney knew to be there. Thankfully that die had been cast over the Rubicon, because if Barney had to think about Saint for just a second longer he'd almost certainly have overshot.
Don't get Barney (or, in a more literal sense, Saint) wrong, Saint wasn't the be-all-end-all of his concerns. Barney had trained with clowns, uppercase and lowercase, many of whom played a bigger role in his life at the circus than Saint had. Few of those clowns, however, had been sic'd onto debtors by the Ringmaster with a baton and thirty minutes' time; fewer still had the face of a Renaissance model and the figure of a cartoon heartthrob. As much as Barney understood "fear"1 and "attraction"2, whether or not they were supposed to mix as much as they did in the presence of a Clown was still pretty new territory.
"Scythe would never let me hear the end of a fuck-up. Remember when I got his ear?" Hell of a show, that one. Barney was supposed to stick the eyes, as Scythe and the screeching anxiety at the back of his head loudly reminded him. Should he have shared that story? "Damn, I miss that sunuvabitch." Alright, shut up now. "What's it been, three years?" Why was he like this?
Saint collected Barney's darts, earning another ping from the anxious mass in his block. "Wouldn't even know. Counting the years ain't my forte." God, he even sounded like a vampire on top of looking the part.
Standing almost perfectly still, Saint took his shot, shots, all three of them, trajectory twisting and winding through the air until they found their bullseye, on the board and in Barney's mind's eye.
"Uh…" Okay, out of words, that's a first. All too fitting it's in front of the grimmest Clown of the band. Come to think of it, Barney's silence was making things worse. "Yeah, that's a neat trick. You'll have to show me how to, you know if you want to show me, do that. Maybe not for an act, I don't know if that meshes with the Barney Brand, you know. Of course-"
"Barney?"
Somehow, that shut him up.
"Do I scare you?"
Barney paused, and looked Saint over. The hourglass figure, distorted just enough to veer into the realm of the fantastic. The rough hands, painted fingernails caked with the memories of a dripping red (it smelled of iron) and a viscous black (too runny for Clown milk, too thick for ink). The gentle face near-perpetually marked by a solemnity inappropriate for a Clown, and the way his "facepaint" accentuated every look, glare, gaze, every smile and frown and expression inexpressible in the span of a single word.
"… a little?"

… alright, you sure you want me to continue that story? In short, it's a few months of me being a little less talkative than usual as I navigate the fact that I desperately want to bone a Clown, followed by me… boning a Clown, I guess. What can I say, Saint only vaguely looked like a demented cartoon and I hadn't exactly handled my breakup with Theodore the best I could.
They're… the turned Clowns have mostly the same body plan, I found. They don't produce milk, no, but they do output a lot of sugar. Of course, they eat a lot of it, too. I don't think the born ones even eat that much. They also don't get tired as much, and they're usually pretty happy. I don't know what Saint's deal was, but I think it had something to do with that sister he lugged around everywhere. But that's a story for another day.
Bred Clowns are essentially show dogs to the born Clown's wolf or the turned Clown's permanent werewolf. That's when the body plans get really weird; actually, ironically, looking at them you never got the feeling you did with the born Clowns, and I think that's because of how Fuller and Ringmaster sculpted them.
Bred Clowns had two purposes: shows and Clown milk. They're all sculpted to fit one or both of those niches. In the process, you lose some of the cartoonish horror of the other Clowns. What you gain is a real piece of work, a powerhouse in whatever chosen field you needed. But, we didn't need all that much.
Of course, we had other clowns, lowercase c. That's me, I think? I never had to drink any Clown milk, and I certainly don't feel all too happy, but I guess the gut thing's worth mention.
Oh yeah, if you don't mind me veering off track a little…

Twenty minutes into alternating between shitting out his intestines and puking with enough force to pull them back in, Barney coughed up something he hadn't remembered swallowing.
Whatever it was was long, longer than Barney was tall, a pale ribbon of what he suddenly noticed were legs the size of his fingers. Hundreds of them, scurrying and clicking and probably some other gerundive that his acute nausea was obfuscating. Weary eyes followed a segmented chitinous shell up to a wicked-looking mole's maw, ten compound eyes staring directly into Barney's.
"Poor human," crooned the… thing, Barney guessed, in a soothing echo across the back of his mind. "You must be shocked. Well-"
***
Something sharp stabbed into Barney's thigh, ripping him away from the deceitfully comfortable clutches of a food (poisoning) coma.
"Hey. Mortal." The… the weird worm Barney only vaguely remembered was poking him. "Doing my big entrance, here, I'd love it if you could keep up."
When Barney rubbed his eyes, nothing happened, so he could have safely ruled out "fever dream". Whatever this thing is obviously cared about the spectacle in relation to itself, so it probably wasn't any Death he knew of. This was… probably a Port-O, and Barney liked to think he had a good memory, so this couldn't have been a new freak… you know, if this was Barney's guardian angel, it'd have explained far too much about the procession of his life.
"… hello? Anyone home?"
Barney opened his mouth to say something, then rushed back to the toilet as his gastrointestinal tract resumed its violent rebellion against the rest of Barney.
***
"Are you done crying, mortal? This is really uncomfortable for me."
Barney had run out of tears around ten minutes ago, and was currently waiting for the sink-water he drank to replenish his water supply in general. "… who the fuck are you?"
"Aha, wouldn't you like to know?" He'll give whatever this fucker is this much: it was ready to do what it came here for. "You may call me Eucestodiel. I am an Awakened, a tapeworm having spent 999 days feeding exclusively on the digestive tract of a mortal, and-"

Huh, what's that?
Wait, seriously? Well sirree, you learn something new every day. I would've thought the intestinal tract would be prime munching, but I guess when you're low on the tree of life you make do without that. God, imagine living without a stomach! I don't know if I could.
Either way, they did tell me that they were-

"-a tapeworm having spent 999 days feeding exclusively on the digestive track of a mortal, and have achieved the power of a god."
"… am I hallucinating you? You seem like the kinda thing a guy would hallucinate after a bad meal."
The tapeworm god (or whatever Barney's mind saw fit to torment itself with) probably would have blinked if they had eyeballs. "You are an odd one, mortal. No matter! Gawk and mock to your heart's content, for you are powerless to stop me." Eucestodiel punctuated their monologue with what was probably a laugh, assuming the appropriate amount of anthropomorphization actually applied.
Barney's body groaned. "Yeah, that sounds about right… yeah, go ahead and do…" … wait. "… what are your plans?"
Oh, hey, Eucestodiel actually blinked.
…
"… you do have plans, right?"
…
***
"Alright, lemme get this straight:" Barney took another swig of ginger ale. "You… became a god."
"The difference is negligible."
"You know, I haven't met too many gods, so maybe." Nothing beat chicken soup from the canteen, except chicken soup from literally anywhere outside the circus; Barney could take that up with Fuller, assuming he wanted his ass whooped. "So, you became a god or god-equivalent, aaaaaaand you don't even have a follow-up."
"I was a tapeworm!" Eucestodiel had elected to munch on a choice selection of mystery meatloaf. "My kind is not the kind to plan and scheme."
"But you became a god?"
"Well, what else was I supposed to do?" Barney wasn't sure he'd ever get used to the sight of Eucestodiel's star-shaped maw in action. "Realistically, it's that or a neuron count in the hundreds."
"I wouldn't know."
"Urghhhh, this is the worst day of my life." Finishing a particularly large chunk, Eustecodiel elected to partially flop over onto its back. "You ruined everything! I was going to look dashing and mysterious and important and you ruined it with your sleep and projectile vomit. I hate you and I wish I was dead."
"I'm sorry to hear that, Eustace."
"Eucestodiel."
"Right, right, sorry, bit of a mouthful and you're the first Eucestodiel I know."
Barney took another swig of ginger ale.
"… you ever seen Back to the Future?"
"No?"
"Want to?"

The story ends there, unless you want me to recap the Back to the Future trilogy. You've seen it, right? No? Okay well, to start things off, meet-
Alright, alright. I do recommend watching it, it's a fun night for the family, or maybe just whoever grew up in the nineties or earlier. I still cannot believe that there are real life people that never had to sit through the 9/11 shitshow. I'm telling you, we got that on some of Fuller's radios, and those things are definitely not "American".
Oh, are we still talking about that, Doc? Sorry, I got a little side-tracked. Although, really, pretty sure I left off at the end of where I was going. Fuller sourced his clowns, lowercase c, from pretty much everywhere. Few freaks, few weirdos, maybe some kid Manny nabbed off the street who only knew how to juggle.
Yeah, the Circus was full of all kindsa weirdos…

"I hate bananas." Eucestodiel stood atop their heaping portion of half-bad spinach and mystery meat, an Empressor upon their rancid throne, frying the minds of any bug that dared challenge that title. "I'm genuinely uncertain how you mortals can stand the taste of it. Don't even get me started on your preoccupation with poisonous root vegetables."
"Eh, humans are flippin' weird, little guy. They eat peppers, peppers, for Pagliacci's sake!"
Next to plate, sitting (with great reluctance) on the edge of the tricolor picnic blanket, was the rubberhose Fleischer graduate ('reject' might have better completed the metaphor, but it didn't complete her) known as Lolly. Her plate, by contrast, was stacked with a funnel cake tower the size of an infant, caked in so much powdered sugar it could have killed Barney. That was, of course, ignoring the Clown milk drizzle that definitely would've killed Barney; the fact that this was half of what's left of her second plate could've sent Atlas into diabetic shock alone.
To think, Barney felt bad for his Peanut Butter and Lucy. "Didn't you used to be human?"
"Oh Marone, you gotta bring that up?" Barney couldn't quite tell which splotches on her face were powdered sugar and which were just her normal skin, but then again it was getting pretty late. "I didn't get it when I was humdrum, sure as flip don't get it now."
Eye contact was a bit hard when your friend was devouring funnel cake like a bear eating a toddler. "I'm telling you, you're missing out. Seriously, the stuffed peppers are the only concession I haven't gotten tired of."
"Why would one stuff a pepper?"
"Ehhhh, mostly convenience." Barney wasn't sure if the moonshine should be getting him drunk or burning him back to sober. "You get more out of the pepper, while adding the kind of taste you need to sell the pepper whole. And props to Willis, his are downright sensational."
"It all seems so decadent." Below them, Eucestodiel's army of mindless insect drones patrolled against further invertebrate incursion. "Is it not all the same in one's stomach?"
"Remind me never to let you brainwash one of the cooks."
Lolly had, inexplicably, finished her second plate and, unbound by the need to keep food off the grass, elected to pace and cartwheel around their spot on the hill. Eucestodiel, meanwhile, seemingly realized that yes, they needed to eat, and dug in. In absence of speech, Barney elected to look up to the emerging stars.
Summer was warm; it's the kind of thing Barney wouldn't have thought about in New York, not before the scent of charcoal wafted through the hills, not before the laughter of dozens saturated the breeze. Not without a blanket against grass, stained with powdered sugar and meat juice and the table scraps of flatworm divinity. Not without the Circus.
Barney closed his eyes, and nearly fell asleep.
…

"I'm gonna ask her."

The Ringmaster, Lolly most likely meant. "Well, it's about damn time. I'm no good at arranging weddings, but I'm guessing-"
"No, Motors, I'm being serious."
Barney blinked himself back to the outside world, to Eucestodiel curled on their plate and to Lolly rocking on her heels in a surprising display of restraint, cartoon face marred by a complex expression. It almost hurt to sit up, though perhaps the blanket just felt that good. "I beg your pardon, Lolly?"
"I…" Lolly's wrists shook, and her heart beat visibly against her sternum. "I dunno, it's been-" and then she cut herself off, freezing for the span of a second, before twirling her head around, to find that the three of them were safe with their secrets, and only then did she continue. "I mean Icky's so, so scary. Just thinkin' of her I get a little chilly, in a good way but also bad, like, I dunno, I'm not good enough."
Barney glanced down at Eucestodiel, who, if the phantom clouds of ancient dreams emanating off them were any indication, was fast asleep. "Come on Lolly, you're good enough."
Lolly was pacing, now, still shooting the occasional glances towards left and right and up and down and anywhere where, Barney supposed, she'd think to find Ringmaster. "I don't feel good enough. I'm, I'm weird and cartoonish and like, I'm not so good with magic like her or talking like you or her, and what if she's already found someone? And you know, she's so flippin' beautiful and funny and talented! Me, I'm some dumb runaway off the streets, I can't wield a baton or speak to…" Lolly collapsed onto the blanket. "What if she doesn't like me?"
"Mm. Lolly, I'm sure you're gonna be fine. It's…" Barney sighed. "Love, relationships, whatever you wanna call it, it's not just a list of statistics. Consider why you like her. It can't just be all the cool shit she does, or you'd be falling for the whole Den."
Lolly rolled over to face the sky, opening her mouth to say nothing.
"You're one of Ringmaster's enforcers, right? Take it from someone who dated your coworker: you actually know her, and she knows you. Me, I think she's scary as hell, but beneath her skin's the same kinda heart I've got beating around my chest. And… and if she's anything like the friends I've made along the way, and I know she is, deep down in that horrifying slash uncomfortably attractive exterior… I don't know. I get the feeling she likes you back."
Barney scratched his beard. "I dunno. Take it from a serial monogamist, with or without a grain of salt."
Lolly said nothing, but the smile she flashed could outshine the moon.

… sorry, think I've got something in my eye. You think we could take a break?

Footnotes
1. And he understood that incredibly well.
2. That, less so.