Ningyo no Hiyaku wa Koi no Jumon

Rishia, a rather careless mermaid, was once saved by a prince.
When she learned that this same prince had fallen ill, she gave up her voice
for a pair of legs to go to him and impart "the mermaid's secret"---.

The tale of Rishia the mermaid, the gardener Eddie, the tender knight Yujin,
and of course Prince Gilbert, the man who saved Rishia's life.

[from DL Site English]