The main focus of the kink, I think, is juxtaposition. Big means nothing if there isn't small to go with it. Ludicrous only gets noticed when it's surrounded by otherwise normal. Gigantic tits are best suited for foxes of a tall, but otherwise average stature. Sometimes you need to, as a storywriter, shove some inconvenient details under the rug when nobody's looking, and other times, you need to point at the plothole directly, wave your magic wand, and make it disappear right before the reader's eyes.
There's a few representations and explanations for hyper as a concept, but the best ones tend to combine the right level of physics and rationality with complete and utter absurdity.