Modify output of custom loop using WP_query

$args = array(
    'posts_per_page' => -1,
    'post_type'      => 'hotwives',
    'post_status'    => 'publish',
    'tax_query'      => array(
        array(
            'taxonomy' => 'category',
            'field'    => 'slug',
            'terms'    => 'slider',
            'operator' => 'NOT IN'
        )
    )
);

Use that as the args for your WP_Query and you should get posts that aren’t in the category taxonomy. It also has the advantage of being expansible to more than one exclude, etc. If you’re using a custom taxonomy, change 'taxonomy'‘s value to the name of that taxonomy.

Docs: WP_Query