1girl, ball, beachball, bikini, bikini_skirt, blue_sky, blush, braid, breasts, brown_eyes, brown_hair, cloud, collarbone, day, frilled_bikini, frills, gekota, hair_between_eyes, himaneko., holding, holding_ball, holding_beachball, looking_at_viewer, misaka_mikoto, navel, outdoors, short_hair, sky, small_breasts, solo, starfish_hair_ornament, sunlight, swimsuit, toaru_kagaku_no_railgun, toaru_majutsu_no_index, wet, yellow_bikini