Satan's Affair

I know this book is meant to be a fun prequel to HA. However, I appreciated the book more because I had already read HA. It answered a few questions but was almost not worth the read for those answers. I feel like the author could've really gotten a good deeper book out of Sibby's story. She is a valuable enough character in HA that I was excited to learn more about her with Satans affair. I got some answers but expected more of her childhood ect.