Scare your trypophobic significant other by placing this where they are most vulnerable :P

I cut the bottom out of the original so you don't make soap scum soup in the shower.
The back is also taller and has key holes for suction cups. I bought 45mm suction cups and the nubbin was a tight fight which I wrestled in with pliers.
OR alternatively there is 2" of flat vertical space above a 1mm ridge to neatly place double sided tape.

Blend file included because I tidied up the geometry of the original,
but also because I think someone should add some horizontal support.
Printed with 4 walls and it still has just a little side to side wobble.