So Shikinami was victim of bullying by Ayanami, who also lost her memories of that when she become a shipgirl? I love this series because you can make a contrast between this past and her canon personality and voice lines.
"I want to protect everyone, my friends and my family.
If I do that, maybe then I'll have a place that would welcome me..."
It was certain during our background check on "Ayanami"
that the girl who would become "Shikinami" was her victim of bullying.
However, we didn't hear anything from the person herself.