@Kamazeustra
 
Perhaps Equestria sees him as an ‘aberration’ of sorts, a non-pony in a world of ponies, and is constantly trying to fix the ‘problem’.
 
As a result it’s constantly bringing magic to bear on him in an attempt to change him into a pony, magic that never manages to take hold(for whatever reason, perhaps Discord gave him an anti-magic shield because while one more pony isn’t funny, LOTS of pony objects most certainly is) and as a result the magic rebounds off onto everything around him, making ponies out of everything nearby.

@Phantom Rider  

 
“-there’s no way the belt isn’t a tiny lamia.”*

Don’t ever change, Badum. Don’t ever change.
 
I wonder what the belt pony thinks of it all. (Because come on, there’s no way the belt isn’t a pony.)

That description XD

At least he didn’t go commando.
 
“We are getting ass stains!”

That moment when your pants start talking to you.

@TheFilmingGuy  
Weirdest or the most functional OC ponies?

Badum makes the weirdest OS ponies

So… Belt-Loop-Ponies hold up Belt-Pony… The Belt-Pony holds up the Pants-Pony… and the Pants Pony is fitted with Belt-Loop Ponies…
 
… WHO IS THE REAL HERO!?

His immediate vicinity always turns into dogscape. Maybe he’s the problem, Twilight’s behavior seems to indicate that the rest of Equestria isn’t like this.

@RustleRustle  
SIR, THE SHIP IS A HORSE TOO!

pff, REAL jeans would take every grass stain as a badge of honor.

@Salamenace  
“Get in the Goddamn ship! Everything’s a horse! The whole planet’s a horse! GO, GO!!”

@RustleRustle  
@Mr. Horrible
 
Yeah, I’m getting cob planet vibes from this.

Underpants knows what’s up.

Don’t anger your pants, especially when she can leave at any time!

Does she at least get along with the washing machine pony?

@Nittany Discord  
He’ll slowly become an amalgamate intelligence, living on in ponyfications of every one of his cells.

@RustleRustle  
Do his organs, blood, and bodily fluids become ponies as well?

There’s only one logical conclusion to this.
 
GMHAA’s skin becomes a pony.

And his belt is a very tiny lamia wrapped snugly around his waist

I don’t know if this was said before but it’s like he’s cursed with the Ponius Touch everything he touches turns pony.

I’m not sure I’d want to live this world where literally every object, substance, and metaphysical concept is actually a sentient creature. Even if they are adorable ponies, it seems like an existential nightmare.

Underpants pony?

Need I say it?
 
Here we go again…