I bought massage cups on Amazon instead of going to sauna.
I bought the massage cups because they were appeared in this sauna Manga which I bought instead of going to sauna.
You really love sauna, don't you?
As a trial, I put one in the back of my neck and see the picture below.
I can't go to sauna with the bruise now...
I hear that they are good for soles as well so I will try it later.