Ore ga Mahou Shoujo da nante Zettai ni Mitomenai

Tsuji Yōka, an ordinary high school boy who cherishes his peaceful everyday life. But one day, Prince Hachi from the magical kingdom, in the form of a dog, fell from the sky right in front of me, and my life was turned upside down. Reacting to the brooch the prince dropped.. lo and behold, I transformed into a magical girl☆.. Wait, I've turned into a girl!? What's more, Satan, the Demon King who came after the prince's brooch, mistook my transformed self for a real girl and declared he'd make me his bride!? I can't change back into a boy.. What on earth is going to happen!?.