What is that on my shower wall?

Good morning everyone,

I have no manual skills or abilities, and this pretty green bathroom.

At least I would like to unscrew this thing on the wall, only: what is it, and: is there any reason against it?

Thank you very much for your help!

That looks like it used to be a shower holder.

You can go ahead and unscrew the screw and don’t have to be afraid. No water will come out at you when you remove the part.

Perfect, Philipp! That was exactly it. Thank you, you are my hero of the day :)

After that, you should best either screw on a new shower holder (universal ones are available from 5 EUR upwards....) and/or at least seal the hole, for example with silicone.