Rei Kiriyama is a 17-year-old youngster who recently moved out on his own, supported by his professional Shogi player pay. Despite his independence, he is still emotionally immature, and his difficulties continue to plague him in his daily life. He has a troubled relationship with his adoptive family, and he has trouble interacting with his peers in high school. Meanwhile, his work life has taken a turn for the worst. His wins and losses are shifting as his record and progression into the rankings begin to slow, owing to the great expectations put on him as the fifth to become a pro in middle school. The three Kawamoto sisters, Akari, Hinata, and Momo, are acquainted with Rei. They, unlike Rei, are content in their humble home, which they eagerly welcome.