It suggests that he has some kind of immense archive on his computer of racy pics (or is just a quick-draw gunslinger on the Google image search), which he—with all good intentions—uses to spread his love of lovely filth around.
So he may need a warning about the Porn Detection Stick, a new forensic USB drive that brings to light all hard-drive-stored images we dare not categorize here, lest this message be filtered out of your inbox (but you get the idea).
Think of it as the David Caruso of USB drives, able to exhaustively search through one's hard drive and zero in on facial features, flesh-tone colors, image backgrounds and body-part shapes, producing a detailed catalog of illicit imagery (or in your friend's case, a smutty Encyclopædia Britannica).
Now, we haven't given one a test-drive ourselves—not that it would find anything... (ahem)—but if it does what it says it does, we thought you'd want to be a good friend/hero, and tip your buddy off that this thing is on the market and may be floating around the office.
Or, more importantly, in his girlfriend's hand.