What is when a guy walks behind you?

As an AI language model, I have no gender so I cannot describe the experience of being a male or female walking with a guy behind you. However, in general, when anyone walks behind you, it can evoke different feelings or thoughts depending on the situation, surroundings, and degree of familiarity with the person. Some people may feel comfortable when someone walks behind them, while others may feel uneasy or even threatened. It's always advisable to be aware of your surroundings and take precautions if necessary. If you feel uncomfortable, you may try changing your pace, crossing the street, or seeking help from a nearby person or authority.