SELECT * FROM user_prof WHERE
gender = 0
AND user_id IN (
    SELECT following_id FROM followers
        WHERE follower_id in (
        SELECT user_id FROM user_prof WHERE gender = 1)
        )
AND user_id NOT IN (
    SELECT following_id FROM followers
        WHERE follower_id IN (
        SELECT user_id FROM user_prof where gender = 0)
    );