This is a compulsively readable Groundhog Day-style story where the protagonist Kazuki Hoshino is caught in an endless repetition of the day a beautiful and mysterious girl transfers into his class. Sounds pretty cliche but this story is surprisingly addictive with many shocking twists. Every time I thought I figured something out, the author would surprise me with a new twist, turning the Groundhog Day trope into something unexpected.
The story is definitely intriguing enough to keep your attention-- in fact, I read this in the span of a couple hours-- but upon closing the book, I felt that there weren't enough explanations for the magical/supernatural elements nor was there any real character development. The protagonist Kazuki was basically a cipher for the reader and we got no real sense of who he is. In addition, the other characters were really thinly developed, mostly relying on familiar anime/manga archetypes. I understand light novels are generally pretty thin on this kind of stuff but I was hoping for a little more than I got.