The two girls are in each other’s personal space, which means that they know each other well and are good friends. They normally stay about the same distance apart, but gradually drift together or apart as they walk. When one person gets ahead of the other, they wait for her to catch up. This means that they have known each other long enough to be comfortable and act normally.

When I talk to someone I know well, I usually stay near the edge of their personal space. I don’t want to be too far away so it seems like I don’t like them, but I also don’t want to make them uncomfortable. When I get too far away, it is harder to talk about things that I normally would, because I don’t want everyone to hear everything I have to say. When I am saying something private, I usually go into someone’s personal space to say it. When I am good enough friends with someone, the boundaries don’t matter as much, because we are both very comfortable around each other. It takes a certain amount of trust to let someone into your intimate space.