I use toilet paper. If I run out I get some more. If the house runs out, (hasn't happened yet) then my wife is in big trouble.
If in the woods, use the toilet paper in my pack.
If off in the car/jeep/truck somewhere, I use the toilet paper kept in the vehicle.
A buddy had an incident once back in high school, and I happened to be there... I learned a valuable lesson.
It may seem silly to be so stocked up on TP.... But I've never gone home wothout a sock on my feet. And my children have never had to wipe with a pine cone.