An Jin, who had an water ability from the apocalypse, transmigrates to an interstellar world and becomes a mermaid captured by His Majesty, the Emperor Norman, on the planet Siao. He is careful to play the role of a pet, but finds that the interstellar humans are extremely obedient toward the mermaids, not like a pet, but more like a mermaid master. His Majesty Norman also discovers something special about the little mermaid as he gets along, and An Jin’s water ability gradually shines through… This is a novel in which a mermaid and human are interdependent with each other, but are unable to communicate, resulting in a heartwarming cognitive difference. The overall story is light and warm, but not lacking in excitement, and the text is very smooth. It depicts a fairytale love story, sweet and warm.