1girl, balancing, ball, bare_shoulders, belt_collar, black_sports_bra, blonde_hair, blush, breasts, cleavage, collar, exercise, exercise_ball, gym, gym_uniform, huge_breasts, kubiwa_(kutan), kutan, long_hair, looking_at_viewer, navel, on_ball, original, pants, ponytail, red_collar, red_eyes, sitting, sitting_on_ball, solo, sports_bra, spread_legs, yoga_pants