1girl, blue_one-piece_swimsuit, brown_eyes, competition_school_swimsuit, cowboy_shot, dated, flat_chest, from_above, grey_hair, hands_on_own_stomach, kantai_collection, kasumi_(kancolle), long_hair, montemasa, one-hour_drawing_challenge, one-piece_swimsuit, school_swimsuit, side_ponytail, signature, solo, swimsuit, twitter_username