Shiverhuahua

The creature stands as a heavily muscled humanoid crowned with the head of a chihuahua. Before it crossed over into monsterhood, it lived simply as an ordinary lapdog.

In its former life the little dog was affectionate and gentle. The transformation warped that nature: extreme pampered miniaturization twisted the animal into a feral state, and it now lashes out from fear and unease whenever it is out in the open. It treats anyone it reads as a threat as an enemy and convinces itself that killing them will restore its calm.

The Association files Shiverhuahua as a Wolf-level danger, though it was billed to the public as a far scarier Demon-level opponent. Its Enhanced Strength alone let it dominate a B-Class hero who could not mount any real defense, and its striking speed was quick enough that the same hero could neither block nor dodge. It was deliberately loosed from captivity to fight the B-Class hero Mad Devil Yankee, a match staged as a wager for rich gamblers with McCoy having fixed the outcome in the hero's favor. Instead the beast proved shockingly strong, thrashing Mad Devil Yankee and coming close to killing him, until Saitama stepped in and finished it with a single lethal blow. Even after his beating, Mad Devil Yankee admitted the monster felt far too dangerous for a mere Wolf rating.