Like a weeaboo thinks they're an anime character, a weeabrony is a brony who thinks that they're a character from the children's show My Little Pony: Friendship is Magic, even using words from the show in their language such as everypony, anypony, etc. and are some are most likely cloppers. They are generally more hated by other bronies like cloppers are, and are usually crucified by anti-bronies.

When you eat dirt for the first time and leave your family to build a shack in the woods

The terrifying offspring between a weeaboo and a brony.