When Tsumugi Takanashi starts working at her father's small production agency, she is unexpectedly appointed as the manager of a new male idol group. Despite her initial surprise at this significant responsibility, Tsumugi is determined to support the seven boys. Witnessing the group's strong teamwork, she is later tasked by her father to eliminate four members due to the belief that managing seven idols is excessive compared to the successful trio in TRIGGER. Refusing to compromise, Tsumugi stands firm in her decision not to cut anyone, valuing each member's unique charm that enriches the group's overall charisma. United as IDOLiSH7, they embark on their journey into the cutthroat realm of idol competition, ready to face the challenges ahead.