"Seishun Butayarou wa Petit Devil Kouhai no Yume wo Minai" (rascal does not dream of little devil kouhai) by Kamoshida Hajime. This is volume 2 of the series, featuring romance base on multiple time loops.
Most other time travel related stories involve shifting the characters' physical presence to a different time, this is one of the rare variants that tried very hard to say that no actual time travel happened. Instead, the characters got a glimpse of the future due to Laplace's demon. The fact that multiple futures exist in response as a result of different actions taken seem to violate the determinism proposed by Laplace's demon, but the book manages to close that hole by saying that everything were merely simulations of the future. This was an interesting concept.
Besides some science fiction bits, the primary focus of this series is still teenage romance, delivered primarily through well paced dialogues. Extra care was taken in this volume to adjust Tomoe's accent in those dialogues as a way to add to her backstory. These dialogues have been mostly preserved in episodes 4-6 of the anime series, unfortunately some of the bits related to the social structures of highschool girls were lost.
The second volume maintains the general structure and quality of the first, and also ends with a lead-in to the next volume. This is just the kind of series that makes me want to read all the volumes all in one go.
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Next (2019-07-11): "Seishun Butayarou wa Logical Witch no Yume wo Minai" by Kamoshida Hajime