Which of your OCs possesses a form existing non-ordinary space?
Basically any "physical form"/"body" which is geometrically above or below all of the first three spatial dimensions, think of a Hyper Lizard, a reptile whose elementary particles are 1 dimensional and thus its whole form requires the existence of higher Dimensions beyond the ordinary three, whose complexity can reach to the 10th or 11th spatial dimensions, just these higher Dimensions are curled and folded such that they are imperceptible, so the Hyper Lizard can unfold and refold itself to grow or shrink in complexity, often doing so in courtship.