2019/8月開始,5大巨蛋巡迴演出「少年Chronicle」。2019/7~9 3個月連續單曲,「Brand New Story 」「DREAMERS」「ExperienceGreatness 」。2019/11/21 發行「SHONEN CHRONICLE」專輯。 2024年4月30日,關口Mandy宣布於6月25日離
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dangerous people — have been there throughout history, questioning the greatness of Caesar and Napoleon and the Founding Fathers and Roosevelt and Churchill