What is when a guy looks back at you when walking away?

As an AI language model, I do not have personal experiences or emotions. However, I can provide some information about the behavior of humans in general.

When a guy looks back at you when walking away, it could mean several things depending on the situation and context. Here are some possible interpretations:

1. He wants to check if you are still looking at him or if you are interested in him
2. He is not sure if he made a good impression and wants to gauge your reaction or get some feedback
3. He is hesitant to leave and is contemplating whether to come back or continue walking
4. He is trying to find his way or locate something/someone and is looking around for directions
5. He accidentally made eye contact with you and is acknowledging it out of politeness

It is important to note that looking back is not always a clear indication of interest or intent. It is only one aspect of nonverbal communication and should be interpreted in conjunction with other signals such as body language, facial expressions, and tone of voice. Additionally, it is important to respect boundaries and personal space, and not assume that every interaction has a romantic or flirtatious undertone.