Authoring, ie portrayed characters and their surroundings do not belong to any product (anime, movie, game), and is entirely an invention of the artist. long hair:
Length is shorter than shoulder length, but no longer than the knee. single:
Images depicting only one character.
No one else should be visible in the picture. miniskirt:
Skirt with a hemline well above the knees, generally no longer than 10 cm (4 in) below the buttocks.