Summary 1: Kuu Shiratori often fantasizes and dreams of her "prince", and longs to meet him as her ordinary school life in the school-city of Academia proceeds. One day, a young man, Kyoshiro Ayanokoji, transfers to her class, and strangely enough, bears a striking resemblence to the prince of her dreams. Kuu is elated, but soon after things start to not go her way, as she soon finds out that Kyoshiro is different from how she imagined him to be. However, after Kyoshiro saves her after she gets caught in the middle of a fight involving mechanical creatures and magic she has never witnessed before, she begins to appreciate him once again, and thus, a beautiful relationship between two young people commences.
Source: Anime News Network
Summary 2: Ten years have passed since the most serious crisis of mankind occurred. The story takes place in the huge academic city Academia symbol of the recovery.
The main character, Shiratori Ku, is a high school girl, who enjoys school life, but thinks her routine life is empty. She sometimes has a recurring dream though, a dream in which she encounters a prince. And while all the students are preparing for the school festival, the prince from her dream appears in reality. And just like in her dream, the prince Ayanokoji Koshiro asks her: Come with me…