I just spent like 10 minutes at near death fighting a skeleton. Chasing it in it's final throws, I was ready to land the killing blow and yet...a guard appeared, killed the skeleton and the corpse immediately disappeared. I've been jilted and this will not go unnoticed.
Great first post. It is intentional that corpses from animals/monsters are removed on death if they are killed by a town guard, in order to prevent guard-farming. However, the mechanics involving how/why guards are summoned may not be correct, I'll have to look into that. Welcome to Renaissance.