2girls, bikini, bikini_top_only, black_bikini, blush, breasts, brown_hair, cleavage, collarbone, higuchi_madoka, idolmaster, idolmaster_shiny_colors, izumi_mei, kaiso_(kaisooekaki), lens_flare, looking_at_viewer, looking_back, medium_breasts, multiple_girls, nail_polish, outdoors, partially_submerged, ponytail, smile, swimsuit, white_bikini