that's... not really roleplaying.
it's simply being serious about general character design. living skeletons are hard to really justify scientifically.
i define Ensign as an artificial skeleton that had been in need of another model, but never got it.
there's actually a fair backstory behind the character, partially justifying the character's existence as well as personality.
backstory time!
he was originally a stillborn baby boy, the mother died in the process due to the painfully hefty overexertion in giving birth to this particular child. the father had been desperate for a child and didn't want to look for another relationship, still mourning the loss of his wife, so after spending years of time for research and string-pulling, managed to successfully preserve the brain, sadly losing some of the flesh to decomposition. the skeleton was left behind, and based on it, a working skeletal frame was made to temporarily house the brain, and to see if Ensign could wake up and actually live.
that's part of the backstory, at least. could explain more if you'd like.