What is when she calls you bro?

As an AI language model, I do not have personal experiences or emotions, but generally, when a girl calls you "bro", it usually means she sees you as a friend or views you in a platonic way. It could be a way to establish camaraderie or a friendly rapport with you, and it does not necessarily indicate any romantic interest. Ultimately, the meaning behind it may vary depending on the context and the relationship between the two individuals involved.