Get a post to now show up on main blog page?

Hey guys, im posting a NSFW babe of the week section on my website, the only problem with this is that i DONT want the NSFW babes to show up on the main page. They should only show up in the NSFW sub-category. Does anyone know how to block a sub-category from showing up on the main page when a new entry is made? if you have another alternative way of accomplishing this, im open to that as well.

thanks guys!