Mermaid Forest - 1x07 - Bone Princess- Followmy.tv

In a flashback to the first year of the Tokugawa shogunate, when Yuta was 120, Yuta remembers Natsume, an apparently 12-year-old immortal girl who works in a market with an old man, whom she calls Pa and who purports to sell mermaid flesh. An itinerant monk who has been searching for Natsume finds her and cuts off her left arm. Yuta carries Natsume and her severed arm back to Pa, who reattaches her arm. In truth, the monk had used a piece of mermaid liver to resurrect Natsume for Pa. When the monk had decided to end Natsume's existence, Pa had run away with her. Yuta doubts destroying Natsume is the right thing to do and offers to take her with him. The monk attacks Natsume and removes the mermaid liver. When Pa sees that the monk has removed Natsume's liver, he picks her up and jumps off a cliff with her. Yuta finds Natsume alive at the base of the cliff, but she turns to bones in his arms. Back in the present, Mana asks Yuta if he thinks she has developed nicely.