How are they watching porn with women who's breasts haven't developed? That's child porn and illegal in most western countries (maybe not France as we saw with that disgusting Netflix movie). Outside of that, if she doesn't feel comfortable, break it off. Personally, relationships are built on trust. If you're snooping around in your partners search history, you're bound to find something you don't like. If I found my partner snooping (good luck - I'm pretty vanilla), I might just end it with them. Who wants to live like that?