First thing is that you don’t use the shower in someone else’s house without asking.
If you haven’t asked about the shower, then you don’t take one until you do.
If you have your hosts’ permission to use the shower, and they didn’t tell you which towels to use, it’s your responsibility to ask. (Which is one big reason why you must ask permission.)
Using the soap in the shower is kinda taken for granted. I’d ask about the shampoo, myself.
Using items that come into direct contact with either the mouth or grungy areas of the body, such as bottles of mouthwash, stick deodorant, and nail clippers, is absolutely verboten if you don’t have specific permission.
And I’d ask about everything else except the Q-tips. (Why wouldn’t they be safe? Unless you or your hosts re-use them, which is an idea that I’d rather not deal with.)
Aside from the towels, the easiest way to deal with all these things is to get a small toiletry bag, and stock it with travel-size (i.e. small) items of the basic stuff you need. Mine has toothbrush, toothpaste, razor, shampoo, deodorant, nail clippers, comb, and a Ziploc bag with a handful of Q-tips.
I thought I’d point out that I’m talking about a situation where you have permission to take a shower, you thought you had the stuff you need, but you forgot something or it turns out you’re missing something. Here’s where the ethics of hygeine come into place.
Well, IAN Miss Manners but generally speaking, If a guest is taking a shower at my place, I assume they will be using the soap, shampoo, toothpaste, and towels. Q-tips, no problem there. They may also have access to nail clippers, hairbrush, toothbrush and deoderant without requiring my express permission but it depends on how intimate I am with this guest. If you ask me to use those things and I’m not having sex with you, my answer will probably be “umm I prefer not.”
As a guest, I would only assume I have permission to use only those things are sorta required for basic cleanliness and I wouldn’t ask to use someone’s toothbrush, nail clippers or deoderant.
If the stayover was planned, you should have brought those things on your own and if it wasn’t, well they can wait until you get to your own place.
That’s just how I feel about it anyway.
As long as they clean the enema nozzle when they’re done, then they’re welcome to it. Oh, and take as many suppositories as you like, but use all you take!