I think you might be right. It looks like if you post a review on a Kobo device, you can use bold/italic or whatever and it displays correctly - but when that review then gets posted on the website, it's in plaintext and shows the HTML tags. That could explain some of the weird characters. And for whatever reason, a group of random people (probably kids?) are using Kobo reviews like social media, including cryptic hints as to where they're going to post next.
Why they'd post it to a book like this one though, I have no idea!
