1girl, beach, bikini, blunt_bangs, blush, breasts, brown_hair, c_(theta), cleavage, collarbone, green_bikini, halterneck, hand_in_own_hair, horizon, idolmaster, idolmaster_million_live!, looking_at_viewer, medium_breasts, navel, outdoors, pearl_hair_ornament, print_bikini, red_eyes, sideboob, sidelocks, smile, solo, straight_hair, strap_gap, string_bikini, sunset, swimsuit, tanaka_kotoha