Hawaiian massage uses long flows strokes to melt away stress and reduce the worries of the now, gently rocking us to a state of bliss and serenity. Little can interfere with that than thoughts of vulnerability around what you are wearing.
A bikini is made of material that is designed with water and suntan lotion in mind, so getting oil on it should not be of much concern. It covers what needs to be covered and is comfortable when lying on your stomach as opposed to a padded underwire bra.
Why not consider wearing a bikini to your next amazing Hawaiian massage, making sure you are at peace with your body being covered and available to be massage all in one outfit! Plus you will look awesome on the massage plinth!