I have a book that I wanted to clean up a bit and erase some ink
(standard ball point pen) written down the spine. Being a tad too
eager, I tried an eraser (standard pencil type) and although it took
off some of the ink, I now have the remnants of the pinkish eraser
color.

Any ideas on how to remove this, and for futures, what's the best way
to remove ink from a printed page or book spine?