This is a story about certain siblings, suddenly-appeared penguins, and the past and the future of this world... The Takakura brothers, Kamba and Syoma, search for PENGUINDRUM by order of a mysterious penguin-shaped hat to save their ill sister Himari. Ringo Oginome keeps realizing that her destiny has been written in a diary. Masako Natsume tries to get her hands on Ringo’s diary to find her new destiny. Keijyu Tabuki and Yuri Tokikago attempt to get back their precious person of fate. All seek the PENGUINDRUM for their own sake and that of someone dear to them. Ten years later... Kamba and Syoma, who rode the train to change fate, momentarily come back from the place their fate took them…
학교에서 아이돌!! 아홉 명의 소녀들이 만드는 청춘 학원 드라마 졸업식 직후, 뮤즈에게 어떤 소식이 날아들었다. 3학년의 졸업을 계기로 활동을 끝내기로 결정한 뮤즈였지만, 그 소식을 듣고 새로운 라이브 공연을 준비한다. 처음 보는 세상을 접하고 다시 조금씩 성장해 나가는 아홉 사람. 이들은 스쿨 아이돌로서 마지막으로 무엇을 할 수 있을까? 얼마 남지 않은 시간 속에서 뮤즈가 발견한, 최고로 즐거운 라이브란 무엇일까?
Yuuta has always been close to his elder sisters, Chiyo and Chinatsu. The only man in the house, he falls in love with the caring and affectionate Chiyo; with her well-endowed body and love of cosplay, she gives her brother everything an adolescent boy could dream of. Envious of her siblings' intimate relationship, Chinatsu soon steps in, seeking Yuuta's attention. As a strong-willed and dominant tomboy, she is the exact opposite of Chiyo and starts picking on him and making aggressive sexual advances. With the situation at home changing dramatically, the siblings must find a way to sort out both their private and school lives and establish a compromise between conflicting interests.
Masayuki's parents have gone overseas, leaving him alone in the house. To his surprise, they have hired Sayaka, a fellow student from school, to work as his maid while they are gone. Masayuki wants his life to be peaceful, but alongside Sayaka's affections he also has to fend off the attention of his kohai, his younger aunt, and his aunt's yandere lesbian admirer.
It's finals time, but tests aren't the only things stressing out Yuuta, who's literally being smothered with affection from his beautiful sisters: Chiyoko, who is feminine, caring, and coddles him; and Chinatsu, a strong-willed tomboy who desperately seeks his attention by picking on him. Who will triumph in this sibling love triangle?
