Shikkari! Chounan
しっかり！長男
Sachiko is the eldest son of the Yamada family, burdened with the responsibility of caring for his younger siblings after their mother's death. He struggles to balance his duties as a surrogate parent with his own desires and adolescence.
His life becomes even more complicated when he meets a mysterious girl who challenges his rigid sense of duty. As Sachiko navigates family obligations, school, and budding romance, he must learn what it truly means to be a responsible eldest son.