Ummmmm...

Just like everything else in nature, sometimes things just don't develop properly. Call it what you will; a mental deficiency, stunted learning, or a handicap. These poor Pimacs victims obviously suffer from a deficiency in their brain development, either through a birth defect or a traumatic experience during childhood. No matter the cause, the effect is the same, a Pimacs effect that causes them to attach to each other, not head-to-head, but some other asset.