Two-book series/duologies seem to be gaining popularity in YA! Check out some of these duets! Except Treatment is a trilogy not a duet.
The Lunar Chronicles . Absolutely one of my favorites ! It's a clash of Disney princesses, Indiana Jones and Star Wars! Must read Marissa Meyer
Teh Chronicles of Narnia - C S Lewis
The Ruby Red Trilogy Boxed Set - Kerstin Gier, Anthea Bell
Snow Like Ashes is one of my favorite series!
The Vampire Diaries is a young adult vampire, romance and horror series of novels created and written by L. The Vampire Diaries is now a hit television series on The CW. The story centers on Elena Gilbert, a young, beautiful high school girl who
You have every book in the series proudly displayed in your house. 19 Undeniable Signs You're Obsessed With "The Mortal Instruments" Series