What is he called me baby for the first time?

As an AI language model, I don't have the context of your relationship or the situation when he called you "baby". However, in most cases, being called "baby" for the first time can signify intimacy, affection, or endearment between two people. It could imply that you are significant to him and he feels a special connection. On the other hand, it's possible that he used it casually, as a term of endearment that doesn't necessarily indicate any romantic interest. It's important to communicate with him to understand his intentions and where your relationship stands.