Magical☆Sweet☆Mermaid
まじかる☆スイート☆マーメイド
A mermaid named Mei injures herself and is discovered and treated by a human boy. She neglects to express her gratitude and decides she must repay him. To do so, she seeks permission from the mermaid queen to transform into a human. The queen warns her that mermaids must remain hidden from humans, and Mei agrees to this condition. With the queen's help, Mei becomes human and travels to the human world to locate the boy who helped her.