It is a world in which "beastmen" exist, creatures who have characteristics of both animals and humans... Fukuyoshi Yugo works as a veterinarian in a zoo. He loves animals more than anything, but he doesn't really get along with people. One day Fukuyoshi discovers a small injured snowy owl and decides to take care of it. He immediately fell in love with this wonderful creature with its unique and beautiful feathers - when suddenly the owl turns into a beastman in front of his eyes!

“Shiro” is struggeling to become a perfect beastman while Fukuyoshi stays by his side, watching and supporting. As they spend time together, they develop a strong bond... A clumsy but caring veterinarian and a beautiful white owl, a one of a kind mysterious and pure love story!