hida tatsuo, akizuki ritsuko, idolmaster, idolmaster (classic), idolmaster 1, 00s, 1girl, alternate costume, antenna hair, arm up, back, backless dress, backless outfit, bare back, bare shoulders, black dress, black gloves, breasts, closed mouth, dress, elbow gloves, evening gown, expressionless, female focus, floating hair, formal clothes, full moon, glasses, gloves, hair down, halterneck, large breasts, looking at viewer, looking back, matching hair/eyes, moon, night, night sky, outdoors, sky, solo