The tantalizing Take A Bow singer "covered up" her bikini with a super see-through fishnet skirt, walking with the Forever singer along the idyllic Hawaiian shoreline.
Brown wore a New York Yankees jersey and super saggy red shorts as he held the Umbrella singer's hand.
Of course, the social media-savvy stunner shared her special day with her fans, tweeting a self-pic with the caption, "Pour it up pour it up! #birthdaybehavior."
Fun fact: Hau`oli L? H?nau translates to "Happy birthday" in Hawaiian dialect.