Here's one this troper just barely got: near the end of step 5, when Doki and Nabi are leaving the airport he dips her as if they were dancing, then lifts her with one arm so she floats through the air, the rides off with her behind him. Now, what 3 Images did Doki dream up in the the first step?
I love that scene so much and you guys are right. It's called a Meaningful Echo so this troper added it to the main page.
Doki starts out seemingly a terrifying stalker, and Nabi a surrendered victim. However, over time it seems they stopped looking at each other as objects in space, such that by their date in step 3, they've started really caring about each other as people rather than as ideas. This means that all of a sudden the intolerance they've been getting isn't just an annoying fact of the moment, it's the rest of their life, so that from then on it's actually terrible. Which leads us to step 4.