Takuya Enoki is living a difficult life for a fifth grader. His mother passed away in a tragic car accident a few months ago, forcing him to pick up the slack and take care of his baby brother, Minoru, as his father works the endless hours typical of a Japanese salaryman. He will have to sacrifice his childhood in order to meet the needs of his little brother. Cooking, cleaning, worrying, and trying to discipline Minoru are some of the tasks Takuya will have on his plate, all while their neighbors blame him for Minoru's constant crying. Meanwhile, he will watch as his friends live their carefree lives, enjoying their free time. It will not be easy and there will be plenty of stumbling blocks, but along the way, he may actually learn the true meaning of family.