Loveperson is a word used to describe that the person one is dating is non-binary. The term was created as a gender-neutral way to describe a non-binary significant other, replacing the “girl” in girlfriend and the “boy” in boyfriend with the word "date."
Similar terms include enbyfriend, joyfriend, theyfriend, datemate/datefriend, partner, significant other, and shipmate. Also see Gender-Neutral Terms.