Due to the nature of kirby’s inflation (inhalation of the air or other airborne elements) Kirby’s anatomy would only make sense to be a large bodily chasm much like the human lung to capture and hold the atmospheric area inside of him.
Kirby also floats, suggesting either A) he is lighter than the atmospheric pressure and gravity affecting him and can propel himself through the atmosphere or B) he is strong enough to conteract those forces. Both of which suggest Kirby is not fat or excess skin, but muscle. He is also depicted as smooth and without imperfections as if to suggest that inflated kirby has no stretching of his skin. Smaller kirby and Larger kirby can have different volumes, indicating Kirby has excess skin which can retract into his body when not in use. Which would be able to reside in the chasm of Kirby, that is contracted and relaxed.
So while he may be soft and squishy when deflated, I think Kirby when he has taken in air is much more like a basketball, firm and stiff thanks to the extension (possible hyperextension) of his muscles. Kirby is softer when not inflated due to the relaxtaion of his muscles although the moistness is a variable I am unable to comprehend at this time.
Thanks for coming to my TEDtalk this is why kirby would actually just eat the knife if you tried to stab him
kianamaiart
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