Ohh it's a pretty unique (slightly confusing) story, great art though
it's been awhile since i read it, but i think the story behind that scene is this guy was trying to figure out why the main girl was so feircely independent, and she told him a story about how when she was little her father drew a circle in the dirt, around her, and told her to wait for him. Then he just walked away. Never coming back.
He waited at home for her to see through the trick, but because she was little and trusting, she waited and waited until it was dark. I dont think it ever tells you what happens after that.