[Books] will visit you at your convenience, whether you are...

[Books] will visit you at your convenience, whether you are lonesome or not, on rainy days or fair. They propose themselves as either transient acquaintances or permanent friends. They will stay as long as you like, departing or returning as you wish. Their friendship entails no obligation. Best of all, and not always true of our merely human friends, they have Cleopatra's infinite variety.