Friends who have been, do you usually have to bring slippers and towels when you stay somewhere ?

Towels are provided, but you need to bring your own slippers and toiletries.

Slippers, be sure to bring slippers. Bring as many pairs as you plan to stay for.

All need to be self-sufficient, these are not provided. Various toiletries also need to be self-sufficient and taken for use. Most accommodations will provide towels.

Europe doesn't provide slippers and toothbrush toothpaste. I stayed in homestays throughout the trip, and the floors were as clean as in Japan. You can go barefoot, and even the landlord takes off their shoes to enter. However, I still spent 5 yuan on a pair of plastic slippers on Taobao. They provide towels, and I suggest bringing more packs of tissues. You can use them on the train and at your accommodation. I found that homestays provide fewer tissues and more kitchen rolls.