Sei Shonagon, for instance, was dreadfully conceited. She thought herself so clever, and littered her writings with Chinese characters, but if you examine them closely, they left a great deal to be desired.
— Murasaki Shikibu Diary
The Alpha Rich Bitch
at a court that was full of them. Sei Shōnagon was a lady in waiting to the Heian Japanese Empress Sadako and famous for her learning - which as Murasaki points out was tissue paper thin - as well as her wit which was unkind but very genuine. Sei was good company if you were her social superior or one of the few people she genuinely liked. Otherwise... not so much.
While we know a great deal about what she was like and how she thought from The Pillow Book
we know practically nothing about her life. She was certainly a member of the Kiyowara family, probably a daughter of Kiyowara no Motosuke. She may
have been briefly married to one Tachibana no Norimitsu by whom she had a son and there is a tradition that she died in poverty which is very likely a Karmic Death
inflicted on her by later commentators who disliked her sexual morals which can best be described as loose. Not that there was anything unusual or scandalous about that
in her milieu but her affairs seem to have been unusually free of coyness, heart burnings and perhaps genuine feeling.
Her personality was direct and aggressive by nature, only slightly modified by the shibboleths of her time and place and she was refreshingly free from the self-pity that seems to marinate the writings of other Heian women.