Midori has green braided hair. By his appearance, he can only be seen as a young girl. Midori looks like a human growing feathers and using magic while wielding an axe.
He's huge, even bigger than Firo in her Philo Rial form. In human form Motoyasu's Philo Rials don't differ much, even though among the 3 she's shortest, in Philo Rial form he's the tallest. Even in the Philo Rial Ranch there are other males, but they're not this big. Midori has a "member" truly befitting of a king.