Nasu Kano, known as Nu, has a developmental disability. As soon as she was born, her mother abandoned her in a coin locker. One day, Nu meets Kazuma Kurosako, who has just been released from prison and was attempting to make money by selling substances near Nu's coin locker. Kurosako gradually become interested in Nu and began posting Nu's paintings on social media on a whim. When Kurosako is contacted by a famous overseas artist interested in buying a painting of Nu's, he initially wants to sell it for a high price for his own profit. As he spends more time with pure-hearted Nu, Kurosako gains a more selfless conscious. All of a sudden, Nu collapses from leukemia.