One day an ordinary junior high schooler Shirahime Kanata was ordered forcibly by his mother Konata to do a contract that made him able to transform into a mahou shoujo (magic girl). Moreover, if he dare to cancel the contract his gender would change, or in other words he will change into a girl. Join Kanata, now also know as Kana-tan in his journey of fighting monsters called Noise with his tiny supervisor Moel. He has to wear spats while fighting monsters, just how will he conceal his identity as a boy?