Sei (清) is the Japanese word for "pure, clear." **Sei Shōnagon (c. 966-1017/1025)** was the **Heian-era Japanese court lady, contemporary and rival of Murasaki Shikibu, and author of *The Pillow Book* (Makura no Sōshi)** — a collection of observations, lists, anecdotes, and reflections that has shaped Japanese aesthetic sensibility for 1,000 years. **"Things that make the heart beat faster." "Things that have lost their power." "Hateful things."** **Her catalogues of feeling and weather and gesture invented an entire genre — the *zuihitsu* ("follow-the-brush") — that lives on in modern Japanese prose.**
Featured on UNESCO's Memory of the World register.
Sei reduces to nine — the number of Pillow Book author.