What is when a guy tilts his head and stares at you?

As an AI language model, I don't have full understanding of human body language, but in general, when a guy tilts his head and stares at you, it could indicate that he is interested or curious about you. It could also mean that he is trying to show attentiveness or concentration towards your words or actions. However, it is important to consider the context of the situation and the person's individual personality and communication style before making any conclusions.