"1 Litre of Tears" is a dramatic and heartfelt story about a young girl's struggle with a debilitating disease. As she learns to cope with the challenges of her condition, she inspires those around her with her determination and zest for life. Despite the hardships, she remains positive, spreading hope and love to everyone she encounters.

15-year-old Aya Kito was an ordinary girl, the daughter of a family who works at a tofu shop, and a soon-to-be high schooler. However, odd things have been happening to Aya lately. She has been falling down often and walks strange. Her mother, Shioka, takes Aya to see the doctor. How will Aya react when told about her disease? And how will Aya live from now on?