Sagishi

In a certain kingdom's knights order, there's a young man who's slightly different from the others. He is able to use a very special magic called "puppeteering" which allows him to manipulate his own body. Using this magic, he is always protecting a friend who always gets mistaken for a girl. Except, the "real" girl in this story isn't his friend; it's him! Impersonating a boy; his age, his status, his life-span, it's all a lie! His friends get flustered by his ability to do unbelievable things, like fly in the sky! A fantasy about the Knight Ruzée with a big secret.

(Source: Alpha Manga)