1girl absurdly_long_hair air_bubble blue_background blue_eyes blue_scales bubble closed_mouth colored_skin commission fins full_body gem gradient_background green_gemstone green_hair head_fins highres long_hair looking_at_viewer mermaid monster_girl original purple_skin sakutake_(ue3sayu) scales simple_background skeb_commission solo translucent_hair underwater very_long_hair white_background