If they have a short lifetime then there's probably no need to worry about them - they'll be summoned, do their job and then disappear back from whence they came. If they're permanent, then they could be treated as NPCs?
They'd probably be your NPC's. The summoning/animation doesn't take very long, but that doesn't have to mean the duration of the spell is as short. Actually I'm not quite sure how that would be treated, is it a duration 1-2 for the summoning or is that also the lifetime of the summoned creature? Would probably make sense to make a spell summoned creature live as long as the duration, while a ritual summoning would last longer or even be permanent.
