Dr. Nick: A rare shot of LCL within a plug acting like a liquid should.
Sailor Star Dust: Despite her air of calm, Rei was just as nervous about this as anybody else. It goes to show that people who call Rei nothing but an "emotionless doll" miss the point of her character.
Kendrix: She was holding her breath/scared a bit, but thinking of Gendo gave her strength. She doesn't fear him as a controlling person or anything at this point - He makes her feel safe.
The two are presented as a working team here, there's something between the two of them that no one else (not even Ritsuko) can enter into - Rei is more than a tool, but something like a daughter.
Additional Commentary
thewayneiac: Perhaps I shouldn't bring this up as its originator has disavowed it to a large extent, but there was once an extensive debate about the properties of LCL.
Dr. Nick: In all honesty, that is a terrible thread full of Broken English and classic ANF trolls, and I can only recommend it for the morbidly curious. If there's supposed to be some sort of consistent logic in how the LCL behaves within an entry plug, it's not elaborated enough in the show.