Added a keyhole slot onto danieloliver's Dog Hook to hang it from a screw or nail for increased mounting strength.
As Daniel said, you can use this to hang things behind the bathroom door, but I say go all out: hang it in front of or on the bathroom door. Pretty sure this won't work on any door other than a bathroom door, as the base model only promises to work behind a bathroom door. I'll update this if I can get it to work on any other doors.
Printed with three perimeters for increased strength in the tail, which is designed more to be dog-like than structurally stable.
The slot is 10mm deep total, the screw head sits 5mm away from the wall.
The author remixed this model.