I opened my Kindle app last night, and the book is still there.
This time it's actually in the Quick Reads section.
You would think, since I've complained about it, that they would make sure I didn't see it again.

I don't want to give Amazon any more of my money, but I also want to be able to read the books I've bought in the past without being confronted by that dangerous content.

Two things need to come out of this - a customer side 'Not interested' button, and parity in Amazon's product policies.

They should not have something like that on the site, but I'm told it's under control and will be dealt with imminently. Just sucks that I apparently can't read my books in the meantime.