Alto Estenia is a boy who dreams of becoming a hero. He enters an academy that trains dragon knights, but is spotted by a nobleman and bullied. The people around him and his teachers turn a blind eye, and he becomes physically and mentally exhausted. One day, however, he meets a girl and she falls in love with him at first sight. The girl, Justina, declares in front of the whole school that she will follow Alto and enter the academy. “From now on, I will be Alto’s cavalry dragon!” Justina’s true identity is the transformed form of the divine dragon Bahamut. The sweet school life of the divine dragon girl and the kind-hearted dragon knight boy begins!