An alternative reality version of Ayanami Rei that appears in the final episode of Neon Genesis Evangelion, "The Beast that Shouted 'I' at the Heart of the World".
She appears in a different school uniform than normal (with a brown or yellow sweater vest , white short-sleeved dress shirt, red necktie, and black or grey skirt).
She also has a much more emotive and assertive personality than Rei typically has. Because the scene she appears in is a parody of the stereotypical "crash into the girl hurrying to get to school" meme, she is often depicted running with a piece of toast in her mouth.
Because Rei shares a voice actress with Lina Inverse from Slayers (which originally came out about the same time as Evangelion), and because this alternate version of Rei seemed to share Lina's personality and thus sounded very similar, the Japanese fan community nicknamed this version of her as "Lina Rei".