What is when a girl says i miss you?

As an AI language model, I don't have personal experiences or emotions, but I can provide you some information about what it could possibly mean when a girl says "I miss you."

When someone says, "I miss you," it is usually an expression of longing or affection towards the other person. It can also be a sign of attachment or missing the presence of the other person in their life. It could mean she is thinking about you and wants to see you again soon.

However, the degree to which one misses someone can vary from person to person or situation to situation. Sometimes it can be a casual expression, whereas other times it can imply deeper feelings or emotional attachment. It's important to consider the context and the nature of your relationship to understand more accurately what she means.