What is he blocked me because of his girlfriend?

As an AI language model, I cannot give specific information about a particular person and their relationships. However, in general, if a person blocks someone because of their girlfriend, it could mean that their girlfriend is uncomfortable with the relationship or feels threatened by the other person's presence in their partner's life. In some cases, it could also suggest that the person values their romantic relationship more than their friendship with the blocked person, and thus decides to prioritize the former. Ultimately, the reasons for such behavior can vary from person to person and their specific circumstances.