I don't ALWAYS leave Luna in clothes. She is hypoglycemic though and my doctor did say she would get the shivers pretty easy, so she has a little short sleeved thermal I leave on her, If we go outside or if we have company I put on her pretty sweater and at night I have just a plain white T to keep her warm. But she is "naked" most of her time and just wrapped in a blanket on my lap.
It is fun to dress them though =D