Fish
I am a fish not only because I am a piscean or because the symbol depicts two fishes pulling at opposite directions, but I swim in water.
Swimming in water is much more easier for a fish than to live outside it.
In thin air or thick love the fish can get bruised; water is best suited for its temperement because it is frictionless, for example.
I am also a fish because I drink like one and the proximity of water makes me calm.
Water inside and outside; above and below.
I do not breathe but can provide you with bubbles of life. But unless you are a fish yourself, in which case your agility would make you as slippery as I am, living with me is a remote possibility.
But then there is always the aquarium and I promise you that I am crunchy.
