I'd assume that any alchemical concoction created by Frondale's is safe to consume, regardless of the materials used in the making. Whether that's because the potation itself has sterilized any harmful maladies lingering on the ahriman wing or if the ahriman wing (using this example) is just outright "safe" to eat after the voidal soul is expelled, I don't know.
Something else to consider: many voidsent entities cross over onto our plane by inhabiting dead bodies or tissue. Succubi force their souls into the bodies of dead women, ahriman and deepeyes inhabit the eyes of dead animals, arch demons from rotting farm animals, while mindflayers aren't so terribly picky and will inhabit just about any dead humanoid body.
So if an ahriman inhabits a dead squirrel, but then the ahriman is killed, is there any part of that original squirrel left? Idk, I still wouldn't risk it.
Something else to consider: many voidsent entities cross over onto our plane by inhabiting dead bodies or tissue. Succubi force their souls into the bodies of dead women, ahriman and deepeyes inhabit the eyes of dead animals, arch demons from rotting farm animals, while mindflayers aren't so terribly picky and will inhabit just about any dead humanoid body.
So if an ahriman inhabits a dead squirrel, but then the ahriman is killed, is there any part of that original squirrel left? Idk, I still wouldn't risk it.
