If you watch the anime demonbane. or rather go wiki demonbane. you'll realise that humans have mystical powers much like soccerers and they get more powerful with the help of a book. called a grimorie, which is like textbooks except they impart powers beside knowledge.

these books also have feelings and they can put forth human appearances. but why are all the books females. and 2 of the characters fall in love with their books.

and they probably end up fucking.

sick.

fucking a textbook.