2girls :d arle_nadja artist_request bandeau blue blue_background blue_eyes blue_hair breasts brown_hair carbuncle_(puyopuyo) caustics checkered checkered_background child cleavage diving_mask diving_mask_on_eyes diving_regulator dolphin fins flippers goggles head_fins large_breasts long_hair madou_monogatari mermaid monster_girl multiple_girls official_art open_mouth puyopuyo scuba scuba_tank see-through seriri_(puyopuyo) smile snorkel underwater