About朱と 鷺き 子こ Tokiko
Tokiko (朱鷺子) is a minor, unnamed character who only appears in Curiosities of Lotus Asia. She is probably just one of the many weak youkai in Gensokyo, but seems to value and enjoy books.
Her true name is unknown, but Tokiko (朱鷺子) is a popular name for her among the fanbase. toki (朱鷺) means "crested ibis", a bird which she resembles in appearance and ko (子) means "child". Also, she was referred to on the Japanese Wikipedia on the Curiosities of Lotus Asia article as the "Unnamed Book-Reading Youkai" (名無し本読み妖怪 Nanashi hon yomi yōkai) and later as "The Youkai Who Read a Book" (本を読んでいた妖怪 Hon wo yonde ita yōkai). "Unnamed Book-Reading Youkai" is, however, still a popular name to refer to her.
In Curiosities of Lotus Asia, Tokiko has white hair that is partly blue, red eyes, and wears a black dress with blue trim. She also appears to have wings on her back, small horns on her head, and what appears to be a single wing on the rear of her head, possibly meant to represent the ibis' crest on the back of its head.