It’s from God emperor of dune, i think it’s the fourth book in the series by publication, but not chronologically.

I guess this might be a spoiler if they eventually make it a movie, but basically, the son of Paul merges himself with a sand worm and becomes effectively immortal. It’s both interesting and bizarre.

There’s a lot more to it than that but i don’t want to ruin the story for anyone

Looks like a Milchkaffee, which is kinda like a cafe au lait