Erika is going to really regret not taking any courses about necromancy, or even just spending a few hours going through information wormholes on the internet, because breaking an undead thing's bones really doesn't have any effect on its function. So she's really not doing anything useful--and she is about to have a much worse time, as the corpse already on her lunges forward, mouth opening to sink its teeth into whatever it can find.

The body in the bed isn't quite dead yet, still jerking through its final spasms of life--more animate in dying than it had been while still alive. There's probably a metaphor there.

The only living Foster is already working on the next step, through, lifting his paw to bare his palm to his teeth, ready to slice it open the second this body is dead.