Happy of Fairy Tail was summoned to another world and became a hero! And its inhabitants aren’t human… They’re animals, with ears and tails to match! Guided by a mysterious talking heart, Happy soars through the skies of this new world, helping the friends he’s making along the way, like a cute bunny, an alluring fox, and even a dog that scares him! What is this place? And will Happy ever make it back home to Natsu and the rest of Fairy Tail?! A new adventure begins through uncharted territory, with Happy as the star and artwork by Kenshiro Sakamoto, creator of Pitch-Black Ten!
Happy was sent to the past through the power of the Three Sacred Treasures! There, in Sciencity, he meets Marice, a human girl shut away in a tower. She's been using her magic, Evolution, to make "Marice Friends": animals that can walk and talk like human beings. But General Star has been performing cruel experiments on the Marice Friends and using them as living weapons! Happy joins forces with Marice's guardians, the Three Beast Musketeers, along with Foxy and a young Tortoise, to try and break Marice out and save the animals. Will they succeed...?!