nvm, I got it to work with a normal WP_query, must have botched it up when I tried earlier.
However it now loops all posts from all categories, is there anyway I can get the category in question from some “category_slug” or category_id function?
What I want is something like this:
$args=array(
'post_type' => 'customposttype',
'category_name' => category_id() // <-- this
);
$my_query = new WP_Query($args);