Honzuki no Gekokujou: Shisho ni Naru Tame ni wa Shudan wo Erandeiraremasen - Kizoku-in Gaiden 1-nensei

After the graduation ceremony ends and the library falls quiet once again, Solange reflects on the eventful term that has just concluded—and the many special memories she has made along the way. This new side series explores Rozemyne’s time at the Royal Academy from a variety of new perspectives! In this particular volume, there are stories from the first-year archduke candidates Wilfried, Hannelore, and Ortwin, Rozemyne’s retainers, other Ehrenfest students, and even dormitory supervisors. Events previously untold come to life in these pages! Delve back into Rozemyne’s first year in this recollective volume of your favorite biblio-fantasy, comprising eighteen short stories in total.
(Source: J-Novel Club)
Note: Published after volume 4 and before volume 5 of Part 4.