
Dakara Oniichan to Yobuna tte! is a Japanese novel of 188,703 characters, with 9,635 unique words and 1,840 different kanji. Its difficulty rating on Jiten is average, 2.6 out of 5. The full vocabulary list ranks all 9,635 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.