What is the meaning of "bea girlfriend?"

The phrase "bea girlfriend" is most likely a misspelling or mishearing of "bae girlfriend." "Bae" is a term of endearment, an acronym for "Before Anyone Else," used to refer to someone's romantic partner. Therefore, "bae girlfriend" is a redundant phrase emphasizing that the girlfriend is the speaker's most important person. While slightly unusual, it essentially means "my girlfriend," but with added affection and emphasis on her importance to the speaker.