ok but why did long hair guy cut his nipples?

I assume to make them more sensitive to touch since nipples aren't really men's erogenous zone.

The fresh wounds open probably hurt more/more sensitive. Whenever it heals though, I wouldn't really know how much more sensitive that would make it though (since it'd become scar tissue which is tough and dense).

I think it was probably more of an excuse-reason to draw the bottom in pain / nipple torture tbh...