"Seishun Butayarou wa Bunny Girl Senpai no Yume wo Minai" (rascal does not dream of bunny girl senpai) by Kamoshida Hajime. A blend of quantum physics and romance that works surprisingly well.
The novel opens with brief summary of event on how a girl disappeared, then the first chapter starts with Sakuta encountering a wild bunny girl in the library. The first few pages is a sample of the best features of this novel -- snappy dialogues with a very good tempo, some of which might be juvenile but never really vulgar, all of which were infused with good humor and delivered with slight theatrical exaggeration. There are bits of Enojima scenery interleaved in various places, but mostly it's all about how well the dialogues flow. This was a novel that feels really smooth to read from beginning to end.
The quantum mechanics bits were surprising in that anyone would try to mix this into a love story and actually got it to work. This story is founded on observer effect, around how the world could be changed by changing the observers, and even includes a mention of the double-slit experiment. On this premise, we have Sakuta fighting to restore reality against a thousand other observers who subconsciously perceives a different reality. The methods he chose were easily relatable, but nonetheless epic in its execution. It worked out really well.
For people coming from the anime series, this volume covers episodes 1 through 3 and the first few minutes of episode 4. The anime series is faithful to the novel series, although understandably some dialogues are only available in the original novel. It was obvious to me (especially with the very long title) that this is an anime based on a light novel, and I knew it's exactly the kind of light novel that I want to read just from listening to the first few minutes of dialogues. The extra cover helpfully identified this volume as the first in the series, and the contents totally met my expectations.
Actually there is one unexpected feature -- given that Sakuta appears in every scene, I would have expected that the novel to be written in first person perspective, but that only applies to the first page, while everything that followed was written in third person perspective. Also, the first page that described how "she disappeared before me" and "this is a story of me and her" did not mention Mai as the person who disappeared, so this introduction could be interpreted as either a flashforward or something else. Given the number of open mysteries, this is definitely a series that I will be following.
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