why did she

Appearance
Astolfo is an androgynous-looking boy who is fancily dressed.

Beautiful beyond all compare, he states that his hair ornaments, which seem like something a princess would wear, are an "irresistible proof of friendship" that he uses to restore peace to his depressively mad boon ally, Roland.

He purposefully dresses "as a girl" because he likes cute things

His gender in the servant status was written "le Secret♪".

ok so that explains

whAT? lemme look it up

same??? alstolfo is a he aswell, femboy.