Mermaid Saga Collector's Edition manga volume 1 features story and art by Rumiko Takahashi.

They say that if one consumes mermaid flesh, one can attain immortality. Unfortunately, the more likely result includes becoming horribly deformed or turning into a vicious monster! Even if one were to gain eternal life, however, is such an anomaly a lucky blessing or a terrible curse?

Yuta became immortal when he unwittingly ate mermaid’s flesh, and now he seeks a way to become human again. Hundreds of years later, he encounters a volatile and determined young lady named Mana while searching for a mermaid. Could this mysterious woman hold the key to saving Yuta’s humanity?