Mermaid Forest

Mermaid's Scar (Part II) (1x13)

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Masato tells a captive Mana that he is going to kill Yuta so Mana won't run away. Masato returns to the house, where he tricks Yuta into a booby trap of piano wire, which cuts deeply into Yuta's neck. Masato says that he is over 800 years old and recounts how he used mermaid flesh to make many long-lived companions, all of whom eventually died. Mana escapes and arrives to save Yuta as Masato is beheading Yuta with an ax. Masato shoots Mana, who promises to kill Masato if he kills Yuta. She then collapses. Masato decides Mana is a horrible person and sets fire to the house. Mana awakens in time to drag Yuta's corpse from the fire. Masato drives off in his mother's car, but loses control. As a head-on collision with a truck is imminent, he resolves to find his next companion after he comes back to life. Yuta revives, and Mana cries. Later Yuta asks Mana why she cried when he revived. Mana replies that she was happy.