I'm just going to copy and paste an excellent analysis of previous volumes and how they tie with Mei's letter made by an insightful anon at /u/

Volume 1 - Had Harumin explain how relationships between girls worked at their school and established the deal with fiances. Also had Mei's grandfather as a huge influence on Mei.

Volume 2 - Yuzu learned of Mei's troubled upbringing and dedication to the school from Himeko. Then Shou shows up and we're given the message that there's no one way to live your life.

Volume 3 - Matsuri is there to trigger Mei's jealousy to get her to pursue Yuzu. And while the reader is made to doubt Matsuri's observations, most of them about Mei do ring true to some extent in hindsight.

Volume 4 - Shows that Mei is willing to try to run away from her problems.

Volume 5 - Mitsuko forces Yuzu and Mei to make hard choices, but also introduces the concept of creating your own path with a strong will. Volume also showed how much Mei loved the school, even having to hide her grandpa's photo when kissing Yuzu in his office.

Volume 6 - Yuzu and Mei's relationship intensifies and the ring is given to Mei, which triggers her deeper feelings. Mei acting awkward while comforting Yuzu in the library now has a more negative meaning in hindsight.

Volume 7 - Mei starts actively trying to figure out if she loves Yuzu. By the end of the volume she realizes that she does.

Volume 8 - Sexual tension reaches its peak and is really the "calm before the storm" of volume 9.

Volume 9 - Everything starts to go to hell when Matsuri learns of Mei's engagement. Their friends worry and ponder their future, Yuzu is oblivious to why Mei is acting weird, while Mei is obviously torn. Eventually the guilt overwhelms Mei when Yuzu is thinking of their future together, so timeskip to after Mei bails in order to fulfill her duties. We get a short "where are they now" of the rest of the cast.

last edited at Feb 21, 2018 12:30PM