Boys, Im with Titsup on this.
As other say it may be innocent.
I had 5 and a half years of dodgy photos on computer, and always confronted, as titsup did.
I got the following excuses:
- I cant even imagine how they got there
-they were downloaded accidentally with music from file sharing sites
-I bought a second hand iphone, remember- they must have been on there.
Yes, confront by all means if you are sure it doesnt seem innocent, but on a practical level you need more evidence. Of course you will feel guilty about snooping- this caused me more concern than anything, but I now wish I had done so more thoroughly..
If you find photos on the laptop (i dont know much about iphones), then right click, go down to properties, which should tell you when they were downloaded and from where. I discovered this too late
Look at history, though he may use private browsing, mine did.
Try to look at the cache.
Go to search and just tick pictures- I usually found loads that way, and in received files.
Still, I do hope its innocent. If it isnt, you will start to notice a few other clues, anyway.