Yuta  

, 湧太

A man has been alive for 500 years due to eating the flesh of a mermaid. Despite sharing this experience with other fishermen, only he survived. After consuming the mermaid's flesh, his fellow fishermen became ill or transformed into monsters. Fearing the same fate, Yuta went into denial and eventually forgot about the incident entirely. He lived a normal life until he discovered that while his wife aged, he remained unchanged. Learning of a mermaid who could help him regain mortality, Yuta embarked on a journey to find her. Along the way, he encountered another immortal named Mana, who had also been fed mermaid flesh. He saved her from mermaids and took her as his traveling companion.