A throcken, colloquially known as a billy-bumbler, is a small animal native to All-world. They are described as looking like a cross between a raccoon, a woodchuck and a dachshund, with gold-rimmed eyes. They may be similar to the raccoon dogs of eastern Asia or the African civet.
Throcken are highly intelligent. At least one individual could apparently speak, or at least imitate human speech and recognize individuals by name. However, this is apparently not the norm as Roland Deschain speculates that he may have been ejected from his original pack, likely for the unusual ability.
The throcken Oy joined the ka-tet of Roland Deschain, Eddie Dean, Susannah Holmes and Jake Chambers on their journey to the Dark Tower.