Using a can opener to gouge the marks into the bass works a lot better. <sigh>
If you fill in your profile, (Height - color eyes - DOB) it might be easier to understand the motivation for this request though.
Here's what I know: A Sharpie or even a Marks-A-Lot will bleed and run with polyurethane spray over it.
How do I know? Well - I write my name in the pocket of the bodies I build and every time it gets overspray on it from a polyurethane clear coat, it disfigures and runs.
It might be something you like though - heaven only knows why.
I think getting tattoos on your body would be better - since the bass cannot protest being disfigured.