1girl, ass, barefoot, bikini, blush, bow, brown_eyes, brown_hair, bursting_ass, butt_crack, feet, from_behind, hair_bow, heart, heart-shaped_pupils, long_hair, looking_at_viewer, looking_back, red_bow, shiny_skin, shirai_kuroko, side-tie_bikini_bottom, simple_background, sitting, smile, soles, solo, swimsuit, symbol-shaped_pupils, toaru_kagaku_no_railgun, toaru_majutsu_no_index, twintails, undersized_clothes, young_savage