Quote Originally Posted by KizuyaKatogami View Post
Isn’t it the use of the crystal eye that causes the deterioration? If it is then that’s technically a separate event. She could choose not to use it. My point is that it’s a separate event that has the consequence of death, but after that point it isn’t even mentioned anymore and there’s no signs of deterioration, in fact in shb she gets a power up.
Look carefully at the scenes right after she wakes up after being rescued from the Lifestream. Her eyes have already gone gray. Nobody seems to notice until Matoya asks her about it later. (Also, it's Krile who actually uses the Crystal Eye.)

There's no real consequence for it because it's supposed to take time off of her lifespan, but the game's timeline has barely moved since then. Unless a significant time skip happens, it'll never matter.