I have never quite understood why people get mad at their fella for looking at porn.
I mean it is a 2d image of a woman he can't touch and has little chance of ever meeting let alone having a fling with.
I'd certainly prefer my man to look at porn than to look at some woman on the street as he passes by.
Men quite simply like the shape of a female body - and why not it is cetainly a very attractive thing.
By looking at porn a man can pretend to act a fantasy (all by himself) that he honestly would *not* want to act out in real life and would likely be ashamed of telling anyone that he even fantasised about.
Example man sits at pc looking at a porn page of *naughty naked nikkala* as he jerks off he imagines (idealistically not in realistic terms) that nnn slaps him or pee's on him or some thing you guys don't do in real life.
Once it is over he probably feels ashamed or embarrassed that he even thought about it and he most certainly wouldn't want to really do *that*.
It's a bit like a girl playing with herself on her own and imagining that it is brad pitt or matt damon or some other hot movie star in bed with her - it ain't likely to ever happen and once it is done it is over.
It's a fantasy is all and in a way it is respect to his loved one because he is fantasising over (probably air brushed as well) an image, he is not going out looking for sex or one night stands.
I'd be more worried about a man who didn't look at porn.
Besides, who is the person he comes home to, who does he share his personal space with?
On another note he might not really be looking at lots of porn sites, but a lot of sites for men (gaming, chat, health, etc) actually have pop ups for porn sites and that could well be an explanation as to why there are lots of them in your pc history.
If you choose to ask him about it you must be prepared to trust his answer. Me, personally, i'd just forget about it.