I'm not sure if there's an appropriate place to report these yet, but I've routinely been seeing one ad in particular that in itself violated the TOS for this site.
It is for “Renta!” an e-book manga site. While that in itself is fine, it keep advertising one in particular called “Fooling Around While Zombies Roam” and honestly looks like a few comic squares of two people doing the deed while a zomb1e scratches on the window? And the entire title text is in bl00d splatter.
Considering all of the above definitely violates TOS, and the devs can only do so much when it comes to how ads display I wanted to point it out. It typically is a smaller square advert that shows on the bottom left of the display when viewing wolves.