Answer:
This animated story follows Seita (Tsutomu Tatsumi), a teenager charged with the care of his younger sister, Setsuko (Ayano Shiraishi), after the two children are separated from their parents due to an American firebombing during World War II. Their survival story is both heartbreaking and true to life. The siblings are completely reliant on one another and fight against all odds to remain together and alive.