This is the Thor's Hammer Mjolnir Toilet Paper Holder created by 3D Visuals & Design Co. and available on Amazon. The entirely too expensive toilet paper holder costs $50 and sits on the back of your toilet tank (or any other flat surface). You can see in the picture what this one reads, but there's another product photo below that just reads 'WHOEVER SITS HERE AND HOLDS THIS HAMMER SHALL POSSESS THE POWER OF THOR", so I'm not entirely sure which one you're getting if you actually buy one, since there's no option. I guess it's purchase at your own risk. Alternatively, just don't buy one and do what I do and leave an empty toilet paper roll on the back of the tank like a normal person whose girlfriend hates coming over.
Keep going for the other shot.
Thanks to hairless, who agrees who needs toilet paper when you get enough junk mail?