Milk's old book of ink recipes, written in a fading ink and now irretrievably lost.
Milk tells Carl that she once had a book in which she wrote down several of her recipes. Later she switched to a different type of ink — in an attempt to share her knowledge with a wider group — and it wasn't until recently that she learned everything she had written had faded away.
Some of her best recipes are gone, and she blames herself for not writing them properly, discovering the loss only when she needed them most. Rosetta grunts indignantly at the self-blame. The confession is what motivates her gift of Stayfast Ink and an Adept's Fountain Pen, and her proverb that no single recipe is a feast in itself.
A book whose written contents have faded away to nothing.
The cautionary example behind Milk's gift of permanent ink.