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Nightmare Fuel: Queen of All Oni
Jade being tortured by Lung until she goes completely insane, and then her astral form melts.
At one point during said torture, her eyelidsdissolve.
Jade's PTSD from the above is starting to reach this level, particularly the Freak Out she has when Tohru accidentally recreates the situation — she reduces to an almost animalistic state, and ends up slashing Tohru in the face.
The scene where Jade brainwashes Viper and turns her into the Samurai General is pretty horrifying, and it's made even more so by the fact that the PTSD mentioned above has caused her to completely snap.