In his office, Yuichiro Miki is thought to be the silent, boring salaryman — his expression blank, his presence unnoticed even at drinking-parties. But his sister, Aki, knows the truth: her older brother is quietly the funniest person in the world. From writing clever letters to small acts hidden behind his calm exterior, he holds a secret brilliance. A sibling comedy of appreciation and discovery begins: the younger sister sees the brother everyone else overlooks, and the brother’s hidden life begins to ripple outward.