Description
I really like the dynamic of Sans being an Enderman and Papyrus a skeleton because-
rain- Sans needs cover
Daytime- papyrus needs cover
so to make up for both of these weaknesses, Sans builds dirt huts during the day when they need to rest if they aren't in a forest already, and Papyrus wears his iron armor to help (his cape also has a hood). Sans has a hood of his own from the nitwit villager robe which he can use as temporary cover from rain before Papyrus lends him his iron helmet.
They have a system! Of course they play it really safe, Sans can't really afford to get caught in the rain alone : )