I'm a creature, and I like to be comfortable.
Comfort comes in all shapes and sizes, just like your characters. Think about these little things to give them an extra layer.
I'll use myself as an example.
I hate being sticky. Hate, hate, hate it. I don't care if it's a drop of honey or a blob of jelly or sap from those pesky weeds that pop up like, well, weeds. I have to get it right off.
I don't like the process of getting dirty. I don't mind being dirty after it's apparent it's happening with or without my consent, but I'll go the long way around to keep that first speck of dirt from clinging to my body. Once it's there, I'm down and dirty with the best of 'em.
I hate when I burn my tongue, not only because it leaves those little bumps and nothing tastes the same for a day or so, but also because it makes me feel stupid for doing such a dumb thing. I burn my tongue more often than I should, too, by the way!
I love being outside in the rain - as long as there's no thunder and lightning - and getting drenched. I love even better coming inside, drying off and putting on dry clothes. I love the way it makes me feel - invigorated and cozy at the same time.
I love curling up with a book in a big chair.
I love the first night on clean sheets.
What are some of the little things you love and hate? It's a start for thinking about your characters.
Think about the little things those people you create love and hate. How they get comfy. One little detail might change the direction of your story.