In 2014, after an absence of 40 years, the world’s greatest artistic treasure, the Mona Lisa, again pays a visit to Japan.
Asahina, the museum’s Asia Director, is assigned the task of strengthening its guard against the constant threat that the famous painting will be stolen. He recommends the brilliant appraiser Riko Rinda for appointment as a curator. With magazine journalist Yuto Ogasawara in tow, Riko flies to Paris and easily passes the qualifying test. With Misa Ryusenji, who has also qualified, she sets to work studying her new field, but the more she learns about the Mona Lisa the less certain she becomes, and gradually her powers of judgment are affected. Ogasawara, trying to find out what is going on, learns something astonishing about how, 500 years ago, da Vinci painted a puzzle into the Mona Lisa’s eyes. Now a plot emerges around the painting, involving both France and Japan. Will Riko free herself from the Mona Lisa’s curse and bring the case to a happy end?

In 2019, public anger at media excess has led to censorship of television, newspapers, the internet, books, movies, and music under the 'Media Betterment Act'. To fight the armed 'Betterment Squads' that go around destroying objectionable materials, the nation's libraries have formed their own para-military 'Library Defense'. Iku Kasahara is a new recruit to the defense, where her instructor and squad leader is Atsushi Dojo. At first repelled by his by-the-book approach to leadership, she is gradually won over by his commitment to their battle for 'books' and 'the freedom to know'.

Iku Kasahara joins the ‘Task Force’, the special unit of the Kanto Area Library Defense Force, in search of her ‘prince’, a Task Force member who once rescued a book about to be seized from her by the ‘Betterment Squad’, the paramilitary arm of the Censorship Enforcement Agency. She does not remember what this man looks like, and is attached to the Dojo Squad, where she is trained to within an inch of her life by its martinet of an instructor, Atsushi Dojo.
She meets a Deaf woman, Marie Nakazawa, a childhood friend of an older member of the Task Force, Mikihisa Komaki, who is advising Marie on books she should read. Iku senses that Marie is in love with Komaki. Meanwhile, the librarian Asako Shibasaki is meeting frequently with a curator who has introduced himself as Shuji Asahina. Hikaru Tezuka, also of the Task Force, is fond of Asako, and is not sure what to think about all this.
Now Komaki is arrested by the Betterment Squad. A book he recommended to Marie had not been approved. Komaki is taken away, leaving the other members of the Task Force enraged at his detention on these dubious grounds.
To make matters even worse, Iku’s parents show up. They were strongly opposed to her joining Library Defense, and now her secret—the fact that much of her job involves armed combat—is revealed.
Will Komaki and Marie be torn apart? What fateful decision will Dojo make as confusion engulfs his unit? And how will Iku get through this?

The near future in Japan, in the age officially known as ‘Change for the Better’.
It is a time in which the expression of thought is censored, and the media is tightly controlled. Bearing up under a harsh regimen of instruction under the terrifying Atsushi Dojo, Iku Kasahara is now a full-fledged member of the Library Defense ‘Task Force’, and divides her time between hard physical training and regular library work. Dojo and the rest of the Task Force are ordered to guard a public exhibition featuring ‘The Handbook of Library Law’, a book widely seen as the symbol of freedom, of which there is only one existing copy. The assignment seems easy enough, but this is in fact a trap designed to wipe out and thus disband the Task Force and restore a twisted society to the correct moral path. Can Dojo and his unit defend both an invaluable book and themselves? The members of the Task Force must put their lives on the line in the greatest battle they have ever faced: The Last Mission.

14-year-old Ann has been brought to her mother’s hometown to start a new life following her parents’ divorce. But when her mother tragically commits suicide, Ann, feeling abandoned and alone lashes out in anger. Coming to Ann’s rescue is classmate, Daigo, who makes a promise to her saying, “I’ll always be with you” The two become a couple all through their middle school years until Ann leaves for Tokyo to live with her father. Ann and Daigo attempt to continue their relationship at a distance but Ann is increasingly tormented by memory of her mother’s death. Though she believes Daigo to be her destiny she also worries that she is placing too much pressure on him and may ruin his life, and ultimately decides to break up with him. 11 years later, Ann returns to Shimane to announce her engagement to another man, but is reunited with Daigo, and her heart starts to waver.