"Bungaku Shoujo" (book girl) series by Nomura Mizuki, illustrated by Takeoka Miho. This is an excellent mystery and romance series, targeted at people who really like books.
The "book girl" in this series is Amano Tooko, lover of all literature, and one whose only sense of taste comes from reading and literally eating pages of text. All stories are told from the perspective of Inoue Konoha, author of a bestseller novel, but the outcome of that one single book traumatized him to the point of never writing again, until he met Tooko. This novel series details the various mysteries that these two encountered in their school life, where each mystery and its corresponding solution can be traced to some book.
The mysteries tend to follow a pattern of first determining which book is it, then who plays which role, after which the solution unfolds naturally. Unlike other mystery novels where the detective would occasionally apply experience from similar cases in the past, for this series, the hints always come from some book that is actually published in real life. Most of the books referenced are from non-contemporary Japanese authors, but there is a good mix of western authors as well. It's likely that not all readers are familiar with all background materials to solve these mysteries before Tooko did, but her colorful and sensory description of all text should convince readers to dig deeper. In this sense, this series is both a great collection of mysteries and a gateway to other classic novels.
In addition to the mysteries, this is also a romance novel. Many relationships are built and broken through these volumes. Even though the plot and roles in each volume may resemble classic novels, the reincarnated characters in this series are much more vivid, and often not so discreet in choosing their means to accomplish their selfish agendas. These edgy personalities either drag readers deeper into this novel series or scare them far away, you should be able to set your expectations after reading just volume 1. The relationship between Tooko and Konoha is even more intriguing than these edgy sub characters, and is one that is unique to this novel series. Tooko is a reader who seeks a writer, but Konoha is an ex-writer who seeks something else. This relationship is one that you will want to follow through to the end.
Eight volumes is just about right to account for all the character development, and reaching a satisfying ending all around. But if you need more, four volumes of extra episodes were published after the original series, plus an extra series of three volumes that follow through Konoha as a writer after Tooko has graduated, then another extra volume of Tooko as an editor. And a movie and 3 OAVs after that. It's a really successful franchise.
https://goo.gl/photos/J8krvd3igG8dSNjT9
This is an excellent series overall, and I have been a fan of this author ever since. The same author and illustrator team would go on to produce another similarly structured novel series: "Hikaru ga Chikyuu ni Ita Koro"
I would highly recommend the Bungaku Shoujo series. It's a well-executed story, and all the references got me to read many books that I might not have picked up before. It was well worth the time.
Previous (2016-06-02): "Harem e no Kiyoki Tadashiki Route" by Nomura Mizuki, volumes 0 and 1
Next (2016-06-07): "Planetarian" by Suzumoto Yuuichi