
On her thirteenth birthday, Rian is sent to join the harem of the emperor of Sekisou Kingdom. However, the person receiving her is Akatsuki, who had usurped the throne through "legitimate means" to become the new emperor! Rian is made empress, as she is deemed "suitable," but even though they share a bed, Akatsuki treats her like a child, like a hot water bottle to warm his bed. To help Rian sleep, Akatsuki challenges her with a problem to solve every night!? (Source: Kadokawa, translated)
Juusan Sai no Tanjoubi, Kougou ni Narimashita. is a Japanese novel of 773,884 characters, with 11,659 unique words and 2,026 different kanji. Its difficulty rating on Jiten is hard, 3.2 out of 5. The full vocabulary list ranks all 11,659 words by how often they appear, and you can study them on Jiten or download them as an Anki deck.
Here are some of the words that appear most often in this media, as well as a sample of its rarer vocabulary.