Well just about any search for porn is going to have some linkage involving a number of different kinks that the web sites sometimes try to force...just look at all the sponser, he may not be as into rape or cam shows as you think unless he was specifically going to only web sites that focused on that alone.

As for telling him ...you just tell him, hey want to get a little kinky ... though it sounds like first you need to iron out what relationship issue you allready may have.