sir-argues-a-lot:

Honestly, I’m surprised it took me this long to pick up on what Rei’s feelings towards Asuka really are.

She doesn’t express herself, but apart from some biting remarks, Rei seemed to be legitimately indifferent towards her, while Asuka was pretty clear in her dislike of Rei, and made it explicitly known to us.

But honestly? Rei hated Asuka much sooner and much harder than vic versa. In this scene from episode 14, also known as the clipshow we don’t talk about, Rei makes it very clear that she absolutely despises the color red. She associates it with blood and mankind in her monologue, but given its prominence in the show, there are at least two noteworthy elements heavily associated with the color red.

The first, of course, is Asuka, who is drenched with red in everything she does. This association is easily interpreted as Rei secretly despising Asuka from the start, even if she never acted on it. In this case, it’s interesting to note that while Asuka was rather rude in putting Rei down, Asuka did initially make several genuine attempts to befriend Rei: the most obvious effort in episode 12, when Asuka went out of her way to ensure that Rei could join them in their celebratory dinner. Meanwhile, Rei simply didn’t give a shit about the redhead. She’s ice cold.

The other notable instance of the color red in association with Rei is seen within Rei herself, specifically her eye color. Eyes are the window to the soul, and the use of the color red here is largely symbolic. (A similar instance of such symbolism with regard to eyes is seen with Gendo, whose shades metaphorically close him off from the world.)

Rei’s soul, as we later learn, is not truly hers, but in fact comes from Lilith, a monster which isn’t human at all. Rei detests this, and tries to assert that she is her own self, even if she cannot shake of the feeling of this “wrong" presence within her, serving as one of her primary personal conflicts throughout. Essentially, Rei hates this presence inside her; Rei hates her “soul". Rei hates herself.

It’s quite an interesting visual metaphor, and the subtle allusion to Rei’s actual feelings helps to add to her character.