User blog comment:B214/Question and Answers 4/@comment-24412159-20150126164558/@comment-25935458-20150127010309

Twilight healing can heal any wound (so far) on anyone (human, devil, angel, etc...), but it has not been shown to revive the dead. So as long as the wounded person is alive, then yes. However a ripped out heart, I doubt it (maybe after she reaches balance breaker).

I had to reread Issei's fight with Cao Cao and I did not see anything that said Asia could not heal his wound. Issei did tell Asia to heal the others before him but she did heal him after them. Unless I overlooked it, Phoenix Tears were not mentioned nor was "holy damage"(?).