Kiritsubo no Koi (桐壺更衣)
Her circumstances and position
She was the only daughter between Azechi no Dainagon and his lawful wife, and was Emperor Kiritsubo's Koi (a lady in waiting in the court). She was called Kiritsubo no Koi because she did not have a good backer in kokyu (empress's residence), and was given Shigeisha (Kiritsubo), which was the furthest away from Seiryoden (literally "Limpid Cool Hall," an Imperial summer palace) and inconvenient. Although she lost her father at an early age, she entered the Imperial court, placed with her family's hope for restoration, and her mother, who followed her husband's will, tried hard to get her into the court.
She had an older brother, who became a priest. ('Sakaki' (The Green Branch))
She was not particularly a woman of noble origin, but she won Emperor Kiritsubo's favor, therefore she was shunned by other court ladies and Koi. Moreover, the leading court nobles who supported these women had a sly dig at her mentioning Yang Guifei, and they did visible and invisible nasty things to her. She came to be sickly due to anxiety, and she bore the Emperor a second prince (Hikaru Genji). In summer when Genji was three years old, however, her condition took a sudden turn for the worse, and soon after she went home, she passed away there. The Emperor regretted that he could not even make her nyogo (a high-ranking lady in the court (a consort of an emperor)), so conferred court rank of Jusanmi (Junior Third Rank) posthumously.
There is not a particularly impressive episode concerning her except that she was ill-fated and died young, but her figure cast a shadow over whole chapters of "The Tale of Genji" (Seihen, the main part of a book).
Because the chapter of 'Kiritsubo' (The Paulownia Court) was written in order to pay homage to "The Song of Everlasting Sorrow," there is a view that Kiritsubo no Koi was modeled after Yang Guifei, the heroine in the song, while some people consider that FUJIWARA no Takushi (a consort of Emperor Ninmyo or the biological mother of Emperor Koko) was her model.