This is Burmy Trash-Cloak, see. And Burmy's a real slob. You know the type — his car is full of empty energy drinks, his pants always have pizza stains on them, stuff like that. He doesn't even have a job, he's a dumpster diver. His parents kicked him out, then his girlfriend kicked him out, and now he's living with his friend Trubbish from high school in a trashy apartment with no AC.
Now, when one leads such a filthy life, one is naturally going to pick up some odds and ends. One day as Burmy was crying in the dumpster about how lonely he was, he found two bent metal rods, and for some inexplicable reason they bought him so much joy that he hopped out of the dumpster, turned his life around, and is now a moderately successful garbage truck driver. He married a beautiful Grimer and they have three filthy children.
❤ The End ❤
Storytime aside, ever since I saw my first Burmy in Diamond I always assumed they were crooked metal rods. Think about it: it's cloak is made of garbage, they look like pieces of bent metal that you'd find in a dump or a Fallout game, and most importantly, Wormadam Trash-Cloak is Steel-type. I suppose you could argue that they are bent straws or some other cylindrical object, but to me short metal rods sounds about right.