In practice

(modern au)(kid au)
You and Muichiro were elementary school students and you were the same age, being 7 years old and you were also best friends, you were always together but there was something that you always hid.
One day you were with Muichiro but you told him you had to leave for a second but then you would come back, he curiously followed you to see if he could see your secret.
You retreated and he followed you stealthily until you stopped at a lake to see a giant monster and you took out a strange circular object and you transformed, you had a very cute outfit, (you are a little witch apprentice) when you finished your transformation you said "the cute little witch Yumei is here." The monster begins to attack you, but you easily dodge it.

Ojamajo Doremi