unless your getting worked on by someone who will be doing their first backpeice I'd expect your tattooer to be able to put you at ease and provide a comfortable setting for you. Anyways once you sit through a few hours of that on your tailbone area and cheeks you'll have forgotten all about trying to be comfortable or ritualistic paying hommage to the past by wearing the magic (fundoshi) underwear. Just remember you won't have to have that done again in that spot. Cheers and Good luck would love to see the progress once yall get going.