Minor Modifications (джен)

He builds the tattoo gun because he can, not really expecting to ever use it, but when Mikey realizes just what Donnie’s made out of an old Walkman, some wire, and a busted ballpoint pen, his face lights up like a beam of sunshine through a sewer grate.
“Here,” he says, pointing at a spot high on his left shoulder. “Sensei can’t get mad if it’s the family symbol, right?”