Tsukamoto Mariko is became a 38 years old AKB48 member through an Otona AKB Audition. She was to serve as a center for a TV CM song of Papico 2014 Spring Campaign, Oshiete Mommy. She debuted in a Team 4 theater performace, Idol no Yoake, on her 38th birthday last July 16th and centered Kataomoi no Taikakusen unit song. [Info source: click here]
