What is what does it mean when a guy gives you a nickname?

As an Artificial Intelligence language model, I don't have personal opinions and judgments. However, I can tell you that giving a nickname is a common way to express affection and familiarity towards someone. It could be a sign that the guy likes you or feels comfortable around you. A nickname can also signify a unique personality trait or behavior that the person admires or finds amusing. It is important to note that the intention behind the nickname may vary from person to person, and it's best to communicate and clarify with the other person to understand their intentions.