Group categories by genre

I'm trying to make an anime streaming site and I want to group categories by genre. Lets say the category can belong to several genres e.g actions,horror,mystery and another category belong to actions,horror,romance. How do I group categories into genres? Cause in the most basic structure, we group posts into category. Now i want group categories into genres

Then be able to display the category in the genre by a url such as http://www.domain.com/genre/actions and it will list all categories in it. Here's an example site that has this feature http://www.animetv.org/genres/shoujo/

 

hello there,

in your case you have to play with taxonomy.. the first thing to do is to register the taxonomy : genre
Here is a more info about this : Link

Next, go to Settings => Permalinks.
Set your permalinks to be /genre/%genre%/%category%/%postname%'/ and your category base to be /genre/all/

Now add this Function :

function Blueseodesign_post_type_link( $permalink, $post ) {
    if ( 'post' == $post->post_type ) {
        $genre = 'all';
        if ( false !== strpos( $permalink, '%genre%' ) ) {
            $first_genre = wp_get_object_terms( array( $post->ID ), 'genre', array( 'orderby' => 'term_id', 'count' => 1 ) );
            if ( ! is_wp_error( $first_genre ) && !empty( $first_genre ) ) {
                $first_genre = array_shift( $first_genre );
                $genre = $first_genre->slug;
            }
        }
        return str_replace( '%genre%', $genre, $permalink );
    }

    return $permalink;
}
add_filter( 'post_link', 'Blueseodesign_post_type_link', 10, 2 );

Code (markup):

You will end up with this links :

/genre/genre-name/
/genre/genre-name/category/
/genre/genre-name/category/post-name

But if you would like to list a Categories by Genre, you can use this Function : https://gist.github.com/mboynes/5732600

Goodluck