We'll get into it one of these days. Meanwhile, I can offer you scab samples if you would want 'em. Most of them would contain some foreign pigments, but 'most' is better than 'all,' yeah?

[Compared to blood and hair, scabs are a low-risk substance---and that's lucky for Sam, because even if scabs were easily exploited, her healing tattoos have left scab flakes all over Haven. If someone really wanted some, they'd find some with time, patience, and a piece of scotch tape.]