There is a BL manga where one guy has a secret crush on the other. He thinks the other is into hard stuff so he asks him for help using things like sounding rods and stuff. May have been a salesman, I forget.
When u said sounding rods (which I have no idea wtf it is) I thought of "Let's go ASMR!" it's probably not what you're looking for but idk it could be????
There is a BL manga where one guy has a secret crush on the other. He thinks the other is into hard stuff so he asks him for help using things like sounding rods and stuff. May have been a salesman, I forget.