The origin of this storyline was simple:

I wanted to give Ellen and Nanase more panel-time.

Like, that was it. That was the quest I gave myself.

It has evolved a LOT since that starting point, and is even now continuing to evolve, and where it's going now is something I definitely could not have predicted.

For one thing, George is a significant part of the storyline now. That was definitely not something I would have predicted when I set out with the goal of Ellen and Nanase doing stuff.