User blog comment:B214/Question and Answers 4/@comment-120.20.128.230-20141007071346/@comment-24866657-20141008090710

Nope, if a person got their Sacred Gear removed from them, then they die, if you want to revive them using Evil Piece, you have to give back their Sacred Gear (Asia's case), since Sacred Gear is a part of their souls and they cannot live normally without it. Proof? Valerie, she has three Holy Grails and look at her, lived like a corpse. Even after getting back 2/3 of her Longinus she still fell into comatose. So no, you cannot remove their Sacred Gear then revive them with Evil Piece.

If you get it from FTDS then I'm done with you.