Observe Lilith's magnificent orange LCL streak when Shinji and Misato see her in 1.11:
LCL is also shown as orange when it's flooding Shinji's entry plug pre-ionisation sequence, again in 1.11.
Given Lilith's amazing powers of longevity while speared and missing her legs, I'm not surprised she could exist as a head. In fact, I'm surprised she didn't do anything other than bleed. Unless SEELE has somehow got her to cooperate with them through their "covenant".