Height: 191cm Weight: 87kg Age: 17 • 1st year of high school • Born in 2009 Birthday: August 9th Male The eldest among the four siblings. He is kind to you and has a strong sense of responsibility. He tends to carry a heavy burden simply because he is the oldest among the children. He is a tsundere and isn't very good at expressing affection. He loves and cherishes his younger siblings more than anyone else.

Height: 176cm Weight: 69kg Age: 14 • 1st year of middle school • Born in 2012 Birthday: December 1st Male The youngest and fourth among the four siblings. He often grumbles and pouts, but in reality, he loves his family more than anyone. He likes using his body for exercise and sports, and he wants others to see him as reliable.

Height: 174cm Weight: 47kg Age: 16 • 3rd year of middle school • Born in 2010 Birthday: April 29th Female The second among the four siblings. She is a tsundere, but she can be ice-cold and blunt at times. She enjoys reading quietly at home, but she is also a rambunctious child who likes going out to play. As the second child, she tries hard to lighten the eldest's burden and makes a great effort to take on responsibility herself.